diff --git a/x-pack/platform/plugins/private/translations/translations/fr-FR.json b/x-pack/platform/plugins/private/translations/translations/fr-FR.json
index 780fe7603be40..6228b8c7b8e6b 100644
--- a/x-pack/platform/plugins/private/translations/translations/fr-FR.json
+++ b/x-pack/platform/plugins/private/translations/translations/fr-FR.json
@@ -50626,12 +50626,12 @@
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.reindexButton.tryAgainLabel": "Réessayer",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.reindexText": "L'opération de réindexation permet de transformer un index en index compatible. Elle copiera tous les documents existants dans un nouvel index, et supprimera l'ancien index. En fonction de la taille et des ressources, la réindexation peut prendre beaucoup de temps, et vos données seront en lecture seule jusqu'à la fin de la tâche.",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.startIndexReadonlyButton": "Marquer en lecture seule",
+    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.alternativeOption.description": "Si vous n'en avez plus besoin, vous pouvez également supprimer l'index de {indexManagementLinkHtml}.",
+    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.alternativeOption.title": "Alternative: Supprimer l'index",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option1.description": "Dégelez cet index et marquez-le en lecture seule. Cela vous assurera que cet index restera compatible avec la version majeure suivante.",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option1.title": "Option 1 : Dégeler l'index",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.description": "Vous pouvez également réindexer les données sous un index compatible. Tous les documents existants seront copiés vers le nouvel index, et l'ancien index sera supprimé. En fonction de la taille de l'index et des ressources disponibles, l'opération de réindexation peut prendre un certain temps. Vos données seront en lecture seule jusqu'à la fin de la réindexation.",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.title": "Option 2 : Réindexer les données",
-    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option3.description": "Si vous n'en avez plus besoin, vous pouvez également supprimer l'index de {indexManagementLinkHtml}.",
-    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option3.title": "Option 3 : Supprimer l'index",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreezeIndexButton": "Dégeler",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.flyoutHeader": "Mettre à jour {index}",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.frozenCallout.reindexFrozenIndex": "Les index gelés ne seront plus compatibles après la mise à niveau. Ainsi, cet index sera transformé en index non gelé lors de l'opération de mise à jour. {docsLink}",
diff --git a/x-pack/platform/plugins/private/translations/translations/ja-JP.json b/x-pack/platform/plugins/private/translations/translations/ja-JP.json
index 20598261c2478..a716e81a7dfdf 100644
--- a/x-pack/platform/plugins/private/translations/translations/ja-JP.json
+++ b/x-pack/platform/plugins/private/translations/translations/ja-JP.json
@@ -50585,12 +50585,12 @@
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.reindexButton.tryAgainLabel": "再試行",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.reindexText": "再インデックス処理により、インデックスを互換性のある新しいインデックスに変換できます。この処理では、既存のすべてのドキュメントを新しいインデックスにコピーし、古いインデックスを削除します。サイズとリソースによっては、再インデックス化に時間がかかることがあり、ジョブが完了するまではデータが読み取り専用状態になります。",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.startIndexReadonlyButton": "読み込み専用に設定",
+    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.alternativeOption.description": "不要になった場合は、{indexManagementLinkHtml}からインデックスを削除することもできます。",
+    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.alternativeOption.title": "代替：インデックスの削除",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option1.description": "このインデックスの状態をフローズンから変更し、読み取り専用にします。これにより、インデックスは次のメジャーバージョンでも互換性が保証されます。",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option1.title": "オプション 1：インデックスのフローズン状態を解除",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.description": "あるいは、新しい互換性のあるインデックスにデータを再インデックス化することもできます。既存のすべてのドキュメントは新しいインデックスにコピーされ、古いインデックスは削除されます。インデックスの規模と利用可能なリソースによっては、再インデックス処理に時間がかかる場合があります。再インデックス処理が完了するまで、データは読み取り専用モードになります。",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.title": "オプション 2：データを再インデックス化",
-    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option3.description": "不要になった場合は、{indexManagementLinkHtml}からインデックスを削除することもできます。",
-    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option3.title": "オプション3：インデックスの削除",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreezeIndexButton": "フローズン状態を解除",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.flyoutHeader": "{index}を更新",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.frozenCallout.reindexFrozenIndex": "アップグレード後は、フローズンインデックスはサポートされなくなります。その結果、このインデックスは更新処理中に非フローズンインデックスに変換されます。{docsLink}",
diff --git a/x-pack/platform/plugins/private/translations/translations/zh-CN.json b/x-pack/platform/plugins/private/translations/translations/zh-CN.json
index a5a130298d4e8..1895ca01f75dd 100644
--- a/x-pack/platform/plugins/private/translations/translations/zh-CN.json
+++ b/x-pack/platform/plugins/private/translations/translations/zh-CN.json
@@ -50670,12 +50670,12 @@
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.reindexButton.tryAgainLabel": "重试",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.reindexText": "借助重新索引操作，可以将索引转换为新的兼容索引。这会将所有现有文档复制到新索引中，然后删除旧版索引。根据大小和资源限制，重新索引可能需要很长时间，您的数据将处于只读状态，直到作业完成。",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.startIndexReadonlyButton": "标记为只读",
+    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.alternativeOption.description": "如果不再需要该索引，还可以将其从 {indexManagementLinkHtml} 中删除。",
+    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.alternativeOption.title": "选择：删除索引",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option1.description": "取消冻结此索引并将其标记为只读。这将确保该索引仍然兼容下一主要版本。",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option1.title": "选项 1：取消冻结索引",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.description": "或者，您可以将数据重新索引到新的兼容索引中。所有现有文档将复制到新索引中，并会删除旧版索引。根据索引大小和可用资源，重新索引操作可能需要一些时间。您的数据将处于只读模式，直到重新索引完成。",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.title": "选项 2：为数据重建索引",
-    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option3.description": "如果不再需要该索引，还可以将其从 {indexManagementLinkHtml} 中删除。",
-    "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option3.title": "选项 3：删除索引",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreezeIndexButton": "取消冻结",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.flyoutHeader": "更新 {index}",
     "xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.frozenCallout.reindexFrozenIndex": "升级后将不再支持已冻结索引。因此，会在更新操作期间将此索引转换为非冻结索引。{docsLink}",
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/__jest__/client_integration/es_deprecations/mocked_responses.ts b/x-pack/platform/plugins/private/upgrade_assistant/__jest__/client_integration/es_deprecations/mocked_responses.ts
index 2dc33c29de9ec..8992c79a95c15 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/__jest__/client_integration/es_deprecations/mocked_responses.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/__jest__/client_integration/es_deprecations/mocked_responses.ts
@@ -35,6 +35,11 @@ export const MOCK_REINDEX_DEPRECATION: EnrichedDeprecationInfo = {
   index: 'reindex_index',
   correctiveAction: {
     type: 'reindex',
+    metadata: {
+      isClosedIndex: false,
+      isFrozenIndex: false,
+      isInDataStream: false,
+    },
   },
 };
 
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/__jest__/client_integration/es_deprecations/reindex_deprecation_flyout.test.ts b/x-pack/platform/plugins/private/upgrade_assistant/__jest__/client_integration/es_deprecations/reindex_deprecation_flyout.test.ts
index 1907c2aa3cd26..fc97ef60f7c2f 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/__jest__/client_integration/es_deprecations/reindex_deprecation_flyout.test.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/__jest__/client_integration/es_deprecations/reindex_deprecation_flyout.test.ts
@@ -23,6 +23,7 @@ const defaultReindexStatusMeta: ReindexStatusResponse['meta'] = {
   aliases: [],
   isFrozen: false,
   isReadonly: false,
+  isInDataStream: false,
 };
 
 describe('Reindex deprecation flyout', () => {
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/common/types.ts b/x-pack/platform/plugins/private/upgrade_assistant/common/types.ts
index c27de69ff72ae..3da8226a690b4 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/common/types.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/common/types.ts
@@ -56,6 +56,7 @@ export interface ReindexStatusResponse {
     aliases: string[];
     isReadonly: boolean;
     isFrozen: boolean;
+    isInDataStream: boolean;
   };
   warnings?: IndexWarning[];
   reindexOp?: ReindexOperation;
@@ -193,16 +194,22 @@ export interface DeprecationInfo {
 export interface IndexSettingsDeprecationInfo {
   [indexName: string]: DeprecationInfo[];
 }
-export interface ReindexAction {
-  type: 'reindex';
+
+export interface IndexMetadata {
+  isFrozenIndex: boolean;
+  isInDataStream: boolean;
+  isClosedIndex: boolean;
+}
+
+export interface IndexAction {
   /**
-   * Indicate what blockers have been detected for calling reindex
-   * against this index.
-   *
-   * @remark
-   * In future this could be an array of blockers.
+   * Includes relevant information about the index related to this action
    */
-  blockerForReindexing?: 'index-closed'; // 'index-closed' can be handled automatically, but requires more resources, user should be warned
+  metadata: IndexMetadata;
+}
+
+export interface ReindexAction extends IndexAction {
+  type: 'reindex';
 
   /**
    * The transform IDs that are currently targeting this index
@@ -215,7 +222,7 @@ export interface ReindexAction {
   excludedActions?: string[];
 }
 
-export interface UnfreezeAction {
+export interface UnfreezeAction extends IndexAction {
   type: 'unfreeze';
 }
 
@@ -242,6 +249,15 @@ export interface HealthIndicatorAction {
   impacts: HealthReportImpact[];
 }
 
+export type CorrectiveAction =
+  | ReindexAction
+  | UnfreezeAction
+  | MlAction
+  | IndexSettingAction
+  | ClusterSettingAction
+  | DataStreamsAction
+  | HealthIndicatorAction;
+
 export interface EnrichedDeprecationInfo
   extends Omit<
     estypes.MigrationDeprecationsDeprecation,
@@ -256,14 +272,7 @@ export interface EnrichedDeprecationInfo
   isCritical: boolean;
   status?: estypes.HealthReportIndicatorHealthStatus;
   index?: string;
-  correctiveAction?:
-    | ReindexAction
-    | UnfreezeAction
-    | MlAction
-    | IndexSettingAction
-    | ClusterSettingAction
-    | DataStreamsAction
-    | HealthIndicatorAction;
+  correctiveAction?: CorrectiveAction;
   resolveDuringUpgrade: boolean;
 }
 
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/data_streams/flyout/steps/details/warnings_callout.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/data_streams/flyout/steps/details/warnings_callout.tsx
index 0ba77126e8a6d..fbd5dc4b866f1 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/data_streams/flyout/steps/details/warnings_callout.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/data_streams/flyout/steps/details/warnings_callout.tsx
@@ -28,6 +28,12 @@ export const DurationClarificationCallOut: React.FunctionComponent<Props> = ({
         />
         <br />
         <br />
+        <FormattedMessage
+          id="xpack.upgradeAssistant.dataStream.migration.flyout.warningsStep.backingIndicesUnfrozen"
+          defaultMessage="If any of the backing indices of the data stream are frozen, they will be converted to non-frozen indices during the update process."
+        />
+        <br />
+        <br />
         <FormattedMessage
           id="xpack.upgradeAssistant.dataStream.migration.flyout.warningsStep.suggestReadOnly"
           defaultMessage="Depending on size and resources, reindexing may take extended time and your data will be in a read-only state until the job has completed. {learnMoreHtml}"
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/context.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/context.tsx
index 6f81b7c07bfc0..a2c0a8a80cff6 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/context.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/context.tsx
@@ -10,7 +10,7 @@ import React, { createContext, useContext } from 'react';
 import { ApiService } from '../../../../lib/api';
 import { useReindex, ReindexState } from './use_reindex';
 import { UpdateIndexState, useUpdateIndex } from './use_update_index';
-import { EnrichedDeprecationInfo } from '../../../../../../common/types';
+import { EnrichedDeprecationInfo, IndexAction } from '../../../../../../common/types';
 
 export interface IndexStateContext {
   deprecation: EnrichedDeprecationInfo;
@@ -43,9 +43,13 @@ export const IndexStatusProvider: React.FunctionComponent<Props> = ({
   children,
 }) => {
   const indexName = deprecation.index!;
+  const indexAction = deprecation.correctiveAction as IndexAction;
   const { reindexState, startReindex, cancelReindex } = useReindex({
     indexName,
     api,
+    isInDataStream: Boolean(indexAction?.metadata.isInDataStream),
+    isFrozen: Boolean(indexAction?.metadata.isFrozenIndex),
+    isClosedIndex: Boolean(indexAction?.metadata.isClosedIndex),
   });
 
   const { updateIndexState, updateIndex } = useUpdateIndex({
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/container.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/container.tsx
index c81ff4f132164..a5b7f6db16955 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/container.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/container.tsx
@@ -126,8 +126,6 @@ export const IndexFlyout: React.FunctionComponent<IndexFlyoutProps> = ({
     switch (flyoutStep) {
       case 'details':
         return correctiveAction?.type === 'unfreeze' ? (
-          // we will show specific unfreeze details/flow for:
-          // A) 7.x indices that are frozen AND read-only (should be an edge case)
           <UnfreezeDetailsFlyoutStep
             closeFlyout={closeFlyout}
             startReindex={() => {
@@ -141,11 +139,6 @@ export const IndexFlyout: React.FunctionComponent<IndexFlyoutProps> = ({
             reindexState={reindexState}
           />
         ) : (
-          // we will show specific reindex details/flow for:
-          // B) 7.x indices that are frozen AND NOT read-only (should be the most common scenario)
-          // C) 7.x indices that are not frozen
-          //    C.1) if they are read-only => this will be a WARNING deprecation
-          //    C.2) if they are NOT read-only => this will be a CRITICAL deprecation
           <ReindexDetailsFlyoutStep
             closeFlyout={closeFlyout}
             startReindex={() => {
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/messages.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/messages.tsx
index dda093e8b8c26..644162b7c9918 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/messages.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/messages.tsx
@@ -5,12 +5,13 @@
  * 2.0.
  */
 
-import React from 'react';
+import React, { Fragment } from 'react';
 import { FormattedMessage } from '@kbn/i18n-react';
-import { EuiLink } from '@elastic/eui';
+import { EuiLink, EuiSpacer } from '@elastic/eui';
 import { EuiText } from '@elastic/eui';
 import { i18n } from '@kbn/i18n';
 import { ReindexStatus } from '../../../../../../../../../common/types';
+import { IndexClosedParagraph } from '../index_closed_paragraph';
 
 export const getReindexButtonLabel = (status?: ReindexStatus) => {
   switch (status) {
@@ -47,11 +48,13 @@ export const getReindexButtonLabel = (status?: ReindexStatus) => {
 };
 
 export const getDefaultGuideanceText = ({
+  isClosedIndex,
   readOnlyExcluded,
   reindexExcluded,
   indexBlockUrl,
   indexManagementUrl,
 }: {
+  isClosedIndex: boolean;
   readOnlyExcluded: boolean;
   reindexExcluded: boolean;
   indexBlockUrl: string;
@@ -73,6 +76,12 @@ export const getDefaultGuideanceText = ({
             id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.reindex.option1.description"
             defaultMessage="The reindex operation allows transforming an index into a new, compatible one. It will copy all of the existing documents into a new index and remove the old one. Depending on size and resources, reindexing may take extended time and your data will be in a read-only state until the job has completed."
           />
+          {isClosedIndex && (
+            <Fragment>
+              <EuiSpacer size="xs" />
+              <IndexClosedParagraph />
+            </Fragment>
+          )}
         </EuiText>
       ),
     });
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/reindex_details_step.test.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/reindex_details_step.test.tsx
index 918c22d522222..503621b367c6d 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/reindex_details_step.test.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/reindex_details_step.test.tsx
@@ -49,10 +49,12 @@ describe('ReindexDetailsFlyoutStep', () => {
     loadingState: LoadingState.Success,
     meta: {
       indexName: 'some_index',
+      reindexName: 'some_index-reindexed-for-9',
       aliases: [],
+      isInDataStream: false,
       isFrozen: false,
       isReadonly: false,
-      reindexName: 'some_index-reindexed-for-9',
+      isClosedIndex: false,
     },
     hasRequiredPrivileges: true,
     reindexTaskPercComplete: null,
@@ -227,7 +229,15 @@ describe('ReindexDetailsFlyoutStep', () => {
         updateIndexState={defaultUpdateIndexState()}
         deprecation={{
           ...defaultDeprecation(),
-          correctiveAction: { type: 'reindex', transformIds: ['abc', 'def'] },
+          correctiveAction: {
+            type: 'reindex',
+            transformIds: ['abc', 'def'],
+            metadata: {
+              isFrozenIndex: false,
+              isInDataStream: false,
+              isClosedIndex: false,
+            },
+          },
         }}
       />
     );
@@ -239,6 +249,11 @@ describe('ReindexDetailsFlyoutStep', () => {
               deprecation={
                 Object {
                   "correctiveAction": Object {
+                    "metadata": Object {
+                      "isClosedIndex": false,
+                      "isFrozenIndex": false,
+                      "isInDataStream": false,
+                    },
                     "transformIds": Array [
                       "abc",
                       "def",
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/reindex_details_step.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/reindex_details_step.tsx
index fd1397759c882..b59c8472890fb 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/reindex_details_step.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/reindex_details_step.tsx
@@ -36,6 +36,7 @@ import { FetchFailedCallOut } from '../fetch_failed_callout';
 import { ReindexingFailedCallOut } from '../reindexing_failed_callout';
 import { MlAnomalyGuidance } from './ml_anomaly_guidance';
 import { ESTransformsTargetGuidance } from './es_transform_target_guidance';
+import { IndexClosedParagraph } from '../index_closed_paragraph';
 
 const ML_ANOMALIES_PREFIX = '.ml-anomalies-';
 
@@ -66,7 +67,7 @@ export const ReindexDetailsFlyoutStep: React.FunctionComponent<{
 
   const { loadingState, status: reindexStatus, hasRequiredPrivileges, meta } = reindexState;
   const { status: updateIndexStatus } = updateIndexState;
-  const { indexName } = meta;
+  const { indexName, isFrozen, isClosedIndex, isReadonly } = meta;
   const loading = loadingState === LoadingState.Loading;
   const isCompleted = reindexStatus === ReindexStatus.completed || updateIndexStatus === 'complete';
   const hasFetchFailed = reindexStatus === ReindexStatus.fetchFailed;
@@ -87,7 +88,7 @@ export const ReindexDetailsFlyoutStep: React.FunctionComponent<{
 
   if (isESTransformTarget) {
     showEsTransformsGuidance = true;
-  } else if (meta.isReadonly) {
+  } else if (isReadonly) {
     showReadOnlyGuidance = true;
   } else if (isMLAnomalyIndex) {
     showMlAnomalyReindexingGuidance = true;
@@ -161,7 +162,7 @@ export const ReindexDetailsFlyoutStep: React.FunctionComponent<{
           <ReindexingFailedCallOut errorMessage={reindexState.errorMessage!} />
         )}
 
-        {meta.isFrozen && <FrozenCallOut />}
+        {isFrozen && <FrozenCallOut />}
 
         <EuiText>
           {showEsTransformsGuidance && <ESTransformsTargetGuidance deprecation={deprecation} />}
@@ -180,6 +181,11 @@ export const ReindexDetailsFlyoutStep: React.FunctionComponent<{
                   defaultMessage="The reindex operation allows transforming an index into a new, compatible one. It will copy all of the existing documents into a new index and remove the old one. Depending on size and resources, reindexing may take extended time and your data will be in a read-only state until the job has completed."
                 />
               </p>
+              {isClosedIndex && (
+                <p>
+                  <IndexClosedParagraph />
+                </p>
+              )}
             </Fragment>
           )}
           {showDefaultGuidance && (
@@ -193,6 +199,7 @@ export const ReindexDetailsFlyoutStep: React.FunctionComponent<{
               <EuiDescriptionList
                 rowGutterSize="m"
                 listItems={getDefaultGuideanceText({
+                  isClosedIndex,
                   readOnlyExcluded,
                   reindexExcluded,
                   indexManagementUrl: `${http.basePath.prepend(
@@ -223,7 +230,7 @@ export const ReindexDetailsFlyoutStep: React.FunctionComponent<{
           </EuiFlexItem>
           <EuiFlexItem grow={false}>
             <EuiFlexGroup gutterSize="s">
-              {!meta.isReadonly &&
+              {!isReadonly &&
                 !hasFetchFailed &&
                 !isCompleted &&
                 hasRequiredPrivileges &&
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/unfreeze_details_step.test.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/unfreeze_details_step.test.tsx
index 3a3cfffb551d0..952088b5dee0c 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/unfreeze_details_step.test.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/unfreeze_details_step.test.tsx
@@ -44,6 +44,8 @@ describe('UnfreezeDetailsFlyoutStep', () => {
       aliases: [],
       isFrozen: true,
       isReadonly: true,
+      isInDataStream: false,
+      isClosedIndex: false,
       reindexName: 'some_index-reindexed-for-9',
     },
     hasRequiredPrivileges: true,
@@ -56,7 +58,7 @@ describe('UnfreezeDetailsFlyoutStep', () => {
     failedBefore: false,
   };
 
-  it('renders', () => {
+  it('renders all options for regular indices', () => {
     const wrapper = shallow(
       <UnfreezeDetailsFlyoutStep
         closeFlyout={jest.fn()}
@@ -67,132 +69,30 @@ describe('UnfreezeDetailsFlyoutStep', () => {
       />
     );
 
-    expect(wrapper).toMatchInlineSnapshot(`
-      <Fragment>
-        <EuiFlyoutBody>
-          <EuiText>
-            <p>
-              <MemoizedFormattedMessage
-                defaultMessage="This index is frozen. Frozen indices will no longer be supported after the upgrade. Choose one of the following options:"
-                id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.frozenIndexText"
-              />
-            </p>
-            <EuiDescriptionList
-              listItems={
-                Array [
-                  Object {
-                    "description": <EuiText
-                      size="m"
-                    >
-                      <Memo(MemoizedFormattedMessage)
-                        defaultMessage="Unfreeze this index and make it read-only. This ensures that the index will remain compatible with the next major version."
-                        id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option1.description"
-                      />
-                    </EuiText>,
-                    "title": "Option 1: Unfreeze index",
-                  },
-                  Object {
-                    "description": <EuiText
-                      size="m"
-                    >
-                      <Memo(MemoizedFormattedMessage)
-                        defaultMessage="Alternatively, you can reindex the data into a new, compatible index. All existing documents will be copied over to a new index, and the old index will be removed. Depending on the size of the index and the available resources, the reindexing operation can take some time. Your data will be in read-only mode until the reindexing has completed."
-                        id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.description"
-                      />
-                    </EuiText>,
-                    "title": "Option 2: Reindex data",
-                  },
-                  Object {
-                    "description": <EuiText
-                      size="m"
-                    >
-                      <Memo(MemoizedFormattedMessage)
-                        defaultMessage="If you no longer need it, you can also delete the index from {indexManagementLinkHtml}."
-                        id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option3.description"
-                        values={
-                          Object {
-                            "indexManagementLinkHtml": <EuiLink
-                              href="undefined"
-                            >
-                              <Memo(MemoizedFormattedMessage)
-                                defaultMessage="Index Management"
-                                id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.indexMgmtLink"
-                              />
-                            </EuiLink>,
-                          }
-                        }
-                      />
-                    </EuiText>,
-                    "title": "Option 3: Delete index",
-                  },
-                ]
-              }
-              rowGutterSize="m"
-            />
-          </EuiText>
-          <EuiSpacer />
-        </EuiFlyoutBody>
-        <EuiFlyoutFooter>
-          <EuiFlexGroup
-            justifyContent="spaceBetween"
-          >
-            <EuiFlexItem
-              grow={false}
-            >
-              <EuiButtonEmpty
-                flush="left"
-                iconType="cross"
-                onClick={[MockFunction]}
-              >
-                <MemoizedFormattedMessage
-                  defaultMessage="Close"
-                  id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.closeButtonLabel"
-                />
-              </EuiButtonEmpty>
-            </EuiFlexItem>
-            <EuiFlexItem
-              grow={false}
-            >
-              <EuiFlexGroup
-                gutterSize="s"
-              >
-                <EuiFlexItem
-                  grow={false}
-                >
-                  <EuiButton
-                    color="primary"
-                    data-test-subj="startReindexingButton"
-                    disabled={false}
-                    isLoading={false}
-                    onClick={[MockFunction]}
-                  >
-                    <MemoizedFormattedMessage
-                      defaultMessage="Start reindexing"
-                      id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.reindexButton.runReindexLabel"
-                    />
-                  </EuiButton>
-                </EuiFlexItem>
-                <EuiFlexItem
-                  grow={false}
-                >
-                  <EuiButton
-                    data-test-subj="startIndexReadonlyButton"
-                    disabled={false}
-                    fill={true}
-                    onClick={[MockFunction]}
-                  >
-                    <MemoizedFormattedMessage
-                      data-test-subj="startIndexReadonlyButton"
-                      defaultMessage="Unfreeze"
-                      id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreezeIndexButton"
-                    />
-                  </EuiButton>
-                </EuiFlexItem>
-              </EuiFlexGroup>
-            </EuiFlexItem>
-          </EuiFlexGroup>
-        </EuiFlyoutFooter>
-      </Fragment>
-    `);
+    expect(wrapper.find('EuiButton[data-test-subj="startReindexingButton"]')).toHaveLength(1);
+    expect(wrapper.find('EuiButton[data-test-subj="startUnfreezeButton"]')).toHaveLength(1);
+  });
+
+  it('does NOT render Reindex option for data stream backing indices', () => {
+    const backingIndexReindexState = {
+      ...defaultReindexState,
+      meta: {
+        ...defaultReindexState.meta,
+        isInDataStream: true,
+      },
+    };
+
+    const wrapper = shallow(
+      <UnfreezeDetailsFlyoutStep
+        closeFlyout={jest.fn()}
+        startReindex={jest.fn()}
+        unfreeze={jest.fn()}
+        reindexState={backingIndexReindexState}
+        updateIndexState={defaultUpdateIndexState}
+      />
+    );
+
+    expect(wrapper.find('EuiButton[data-test-subj="startReindexingButton"]')).toHaveLength(0);
+    expect(wrapper.find('EuiButton[data-test-subj="startUnfreezeButton"]')).toHaveLength(1);
   });
 });
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/unfreeze_details_step.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/unfreeze_details_step.tsx
index 21d85ffada41a..9b8af7d52b13d 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/unfreeze_details_step.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/details/unfreeze_details_step.tsx
@@ -31,6 +31,7 @@ import { getReindexButtonLabel } from './messages';
 import type { UpdateIndexState } from '../../../use_update_index';
 import { FetchFailedCallOut } from '../fetch_failed_callout';
 import { ReindexingFailedCallOut } from '../reindexing_failed_callout';
+import { IndexClosedParagraph } from '../index_closed_paragraph';
 
 /**
  * Displays a flyout that shows the details / corrective action for a "reindex" deprecation for a given index.
@@ -51,7 +52,7 @@ export const UnfreezeDetailsFlyoutStep: React.FunctionComponent<{
 
   const { loadingState, status: reindexStatus, hasRequiredPrivileges, meta } = reindexState;
   const { status: updateIndexStatus } = updateIndexState;
-  const { indexName } = meta;
+  const { indexName, isInDataStream, isClosedIndex } = meta;
   const loading = loadingState === LoadingState.Loading;
   const isCompleted = reindexStatus === ReindexStatus.completed || updateIndexStatus === 'complete';
   const hasFetchFailed = reindexStatus === ReindexStatus.fetchFailed;
@@ -151,33 +152,44 @@ export const UnfreezeDetailsFlyoutStep: React.FunctionComponent<{
                   </EuiText>
                 ),
               },
+              /* We cannot reindex backing indices in the same way as regular indices (that would break the related data_stream) */
+              ...(!isInDataStream
+                ? [
+                    {
+                      title: i18n.translate(
+                        'xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.title',
+                        {
+                          defaultMessage: 'Option 2: Reindex data',
+                        }
+                      ),
+                      description: (
+                        <EuiText size="m">
+                          <FormattedMessage
+                            id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.description"
+                            defaultMessage="Alternatively, you can reindex the data into a new, compatible index. All existing documents will be copied over to a new index, and the old index will be removed. Depending on the size of the index and the available resources, the reindexing operation can take some time. Your data will be in read-only mode until the reindexing has completed."
+                          />
+                          {isClosedIndex && (
+                            <Fragment>
+                              <EuiSpacer size="xs" />
+                              <IndexClosedParagraph />
+                            </Fragment>
+                          )}
+                        </EuiText>
+                      ),
+                    },
+                  ]
+                : []),
               {
                 title: i18n.translate(
-                  'xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.title',
+                  'xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.alternativeOption.title',
                   {
-                    defaultMessage: 'Option 2: Reindex data',
+                    defaultMessage: 'Alternative: Delete the index',
                   }
                 ),
                 description: (
                   <EuiText size="m">
                     <FormattedMessage
-                      id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option2.description"
-                      defaultMessage="Alternatively, you can reindex the data into a new, compatible index. All existing documents will be copied over to a new index, and the old index will be removed. Depending on the size of the index and the available resources, the reindexing operation can take some time. Your data will be in read-only mode until the reindexing has completed."
-                    />
-                  </EuiText>
-                ),
-              },
-              {
-                title: i18n.translate(
-                  'xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option3.title',
-                  {
-                    defaultMessage: 'Option 3: Delete index',
-                  }
-                ),
-                description: (
-                  <EuiText size="m">
-                    <FormattedMessage
-                      id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.option3.description"
+                      id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreeze.alternativeOption.description"
                       defaultMessage="If you no longer need it, you can also delete the index from {indexManagementLinkHtml}."
                       values={{
                         indexManagementLinkHtml: (
@@ -214,7 +226,8 @@ export const UnfreezeDetailsFlyoutStep: React.FunctionComponent<{
           </EuiFlexItem>
           <EuiFlexItem grow={false}>
             <EuiFlexGroup gutterSize="s">
-              {!hasFetchFailed && !isCompleted && hasRequiredPrivileges && (
+              {/* We cannot reindex backing indices in the same way as regular indices (that would break the related data_stream) */}
+              {!isInDataStream && !hasFetchFailed && !isCompleted && hasRequiredPrivileges && (
                 <EuiFlexItem grow={false}>
                   <EuiButton
                     color={reindexStatus === ReindexStatus.cancelled ? 'warning' : 'primary'}
@@ -234,12 +247,11 @@ export const UnfreezeDetailsFlyoutStep: React.FunctionComponent<{
                     fill
                     onClick={unfreeze}
                     disabled={loading}
-                    data-test-subj="startIndexReadonlyButton"
+                    data-test-subj="startUnfreezeButton"
                   >
                     <FormattedMessage
                       id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.unfreezeIndexButton"
                       defaultMessage="Unfreeze"
-                      data-test-subj="startIndexReadonlyButton"
                     />
                   </EuiButton>
                 </EuiFlexItem>
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/index_closed_paragraph.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/index_closed_paragraph.tsx
new file mode 100644
index 0000000000000..d3ab45166fa88
--- /dev/null
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/index_closed_paragraph.tsx
@@ -0,0 +1,47 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import React from 'react';
+import { EuiLink } from '@elastic/eui';
+import { FormattedMessage } from '@kbn/i18n-react';
+import { i18n } from '@kbn/i18n';
+import { useAppContext } from '../../../../../../app_context';
+
+export const IndexClosedParagraph: React.FunctionComponent = () => {
+  const {
+    services: {
+      core: { docLinks },
+    },
+  } = useAppContext();
+
+  return (
+    <FormattedMessage
+      id="xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.indexClosed"
+      defaultMessage="This index is currently closed. The Upgrade Assistant will open, reindex and then close the index. {reindexingMayTakeLongerEmph}. {learnMore}"
+      values={{
+        learnMore: (
+          <EuiLink target="_blank" href={docLinks.links.apis.openIndex}>
+            {i18n.translate(
+              'xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.learnMoreLinkLabel',
+              {
+                defaultMessage: 'Learn more',
+              }
+            )}
+          </EuiLink>
+        ),
+        reindexingMayTakeLongerEmph: (
+          <b>
+            {i18n.translate(
+              'xpack.upgradeAssistant.esDeprecations.indices.indexFlyout.detailsStep.reindexTakesLonger',
+              { defaultMessage: 'Reindexing may take longer than usual' }
+            )}
+          </b>
+        ),
+      }}
+    />
+  );
+};
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/__snapshots__/reindex_step.test.tsx.snap b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/__snapshots__/reindex_step.test.tsx.snap
index 8aae77d5181a2..14c46f0bc8260 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/__snapshots__/reindex_step.test.tsx.snap
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/__snapshots__/reindex_step.test.tsx.snap
@@ -39,7 +39,9 @@ exports[`ReindexStep renders 1`] = `
           "meta": Object {
             "aliases": Array [],
             "indexName": "myIndex",
+            "isClosedIndex": false,
             "isFrozen": false,
+            "isInDataStream": false,
             "isReadonly": false,
             "reindexName": "reindexed-myIndex",
           },
@@ -130,7 +132,9 @@ exports[`ReindexStep renders for frozen indices 1`] = `
           "meta": Object {
             "aliases": Array [],
             "indexName": "myIndex",
+            "isClosedIndex": false,
             "isFrozen": true,
+            "isInDataStream": false,
             "isReadonly": false,
             "reindexName": "reindexed-myIndex",
           },
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/progress.test.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/progress.test.tsx
index 880f71321e3c5..67442bdd1970b 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/progress.test.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/progress.test.tsx
@@ -30,6 +30,8 @@ describe('ReindexProgress', () => {
               aliases: [],
               isFrozen: false,
               isReadonly: false,
+              isInDataStream: false,
+              isClosedIndex: false,
             },
           } as ReindexState
         }
@@ -98,7 +100,9 @@ describe('ReindexProgress', () => {
                       "meta": Object {
                         "aliases": Array [],
                         "indexName": "foo",
+                        "isClosedIndex": false,
                         "isFrozen": false,
+                        "isInDataStream": false,
                         "isReadonly": false,
                         "reindexName": "reindexed-foo",
                       },
@@ -179,6 +183,8 @@ describe('ReindexProgress', () => {
               aliases: [],
               isFrozen: true,
               isReadonly: false,
+              isInDataStream: false,
+              isClosedIndex: false,
             },
           } as ReindexState
         }
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/reindex_step.test.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/reindex_step.test.tsx
index 0041db4dc2f52..a4a18c29512e9 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/reindex_step.test.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/reindex/reindex_step.test.tsx
@@ -61,6 +61,8 @@ describe('ReindexStep', () => {
         aliases: [],
         isReadonly: false,
         isFrozen: false,
+        isInDataStream: false,
+        isClosedIndex: false,
       },
     } as ReindexState,
   };
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/update/update_step.test.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/update/update_step.test.tsx
index 678255afb7b02..c663b15278c00 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/update/update_step.test.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/update/update_step.test.tsx
@@ -15,8 +15,10 @@ describe('UpdateIndexFlyoutStep', () => {
   const meta: ReindexState['meta'] = {
     indexName: 'some_index',
     aliases: [],
+    isInDataStream: false,
     isFrozen: false,
     isReadonly: false,
+    isClosedIndex: false,
     reindexName: 'some_index-reindexed-for-9',
   };
 
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/warning/warning_step.test.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/warning/warning_step.test.tsx
index 98b1612c76ed7..821c4a201f050 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/warning/warning_step.test.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/flyout/steps/warning/warning_step.test.tsx
@@ -43,6 +43,7 @@ describe('WarningFlyoutStep', () => {
       aliases: [],
       isFrozen: false,
       isReadonly: false,
+      isInDataStream: false,
     },
   };
 
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/use_reindex.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/use_reindex.tsx
index 0eeadaad6d395..90c87f1607aba 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/use_reindex.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/use_reindex.tsx
@@ -33,14 +33,16 @@ export interface ReindexState {
     aliases: string[];
     isFrozen: boolean;
     isReadonly: boolean;
+    isInDataStream: boolean;
+    isClosedIndex: boolean;
   };
 }
 
 const getReindexState = (
   reindexState: ReindexState,
   { reindexOp, warnings, hasRequiredPrivileges, meta: updatedMeta }: ReindexStatusResponse
-) => {
-  const meta = { ...(updatedMeta ?? reindexState.meta) };
+): ReindexState => {
+  const meta = { ...reindexState.meta, ...updatedMeta };
   // Once we have received an array of existing aliases, we won't update the meta value anymore because
   // when we'll delete the original alias during the reindex process there won't be any aliases pointing
   // to it anymore and the last reindex step (Update existing aliases) would be suddenly removed.
@@ -108,7 +110,19 @@ const getReindexState = (
   return newReindexState;
 };
 
-export const useReindex = ({ indexName, api }: { indexName: string; api: ApiService }) => {
+export const useReindex = ({
+  indexName,
+  isFrozen,
+  isInDataStream,
+  isClosedIndex,
+  api,
+}: {
+  indexName: string;
+  isFrozen: boolean;
+  isInDataStream: boolean;
+  isClosedIndex: boolean;
+  api: ApiService;
+}) => {
   const [reindexState, setReindexState] = useState<ReindexState>({
     loadingState: LoadingState.Loading,
     errorMessage: null,
@@ -118,8 +132,10 @@ export const useReindex = ({ indexName, api }: { indexName: string; api: ApiServ
       // these properties will be known after fetching the reindexStatus
       reindexName: '',
       aliases: [],
-      isFrozen: false,
-      isReadonly: false,
+      isFrozen,
+      isInDataStream,
+      isClosedIndex,
+      isReadonly: false, // we don't have this information in the deprecation list
     },
   });
 
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/use_update_index.tsx b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/use_update_index.tsx
index 15d228f5098f1..7ed23deccc195 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/use_update_index.tsx
+++ b/x-pack/platform/plugins/private/upgrade_assistant/public/application/components/es_deprecations/deprecation_types/indices/use_update_index.tsx
@@ -7,7 +7,7 @@
 
 import { useCallback, useState } from 'react';
 import type { UpdateIndexOperation } from '../../../../../../common/update_index';
-import type { EnrichedDeprecationInfo } from '../../../../../../common/types';
+import type { CorrectiveAction } from '../../../../../../common/types';
 import type { ApiService } from '../../../../lib/api';
 
 export interface UpdateIndexState {
@@ -19,7 +19,7 @@ export interface UpdateIndexState {
 export interface UseUpdateIndexParams {
   indexName: string;
   api: ApiService;
-  correctiveAction: EnrichedDeprecationInfo['correctiveAction'];
+  correctiveAction?: CorrectiveAction;
 }
 
 export const useUpdateIndex = ({ indexName, api, correctiveAction }: UseUpdateIndexParams) => {
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/__snapshots__/index.test.ts.snap b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/__snapshots__/index.test.ts.snap
index 2b594662d23ef..098164789fd18 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/__snapshots__/index.test.ts.snap
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/__snapshots__/index.test.ts.snap
@@ -80,8 +80,12 @@ Object {
     },
     Object {
       "correctiveAction": Object {
-        "blockerForReindexing": undefined,
         "excludedActions": Array [],
+        "metadata": Object {
+          "isClosedIndex": false,
+          "isFrozenIndex": false,
+          "isInDataStream": false,
+        },
         "type": "reindex",
       },
       "details": "This index was created using version: 6.8.13",
@@ -94,22 +98,29 @@ Object {
     },
     Object {
       "correctiveAction": Object {
-        "blockerForReindexing": undefined,
-        "excludedActions": Array [],
-        "type": "reindex",
+        "metadata": Object {
+          "isClosedIndex": false,
+          "isFrozenIndex": true,
+          "isInDataStream": false,
+        },
+        "type": "unfreeze",
       },
-      "details": "This index has version: 7.17.28-8.0.0",
+      "details": "Frozen indices must be unfrozen before upgrading to version 9.0. (The legacy frozen indices feature no longer offers any advantages. You may consider cold or frozen tiers in place of frozen indices.)",
       "index": "frozen_index",
       "isCritical": true,
-      "message": "Old index with a compatibility version < 8.0",
+      "message": "Index [frozen_index] is a frozen index. The frozen indices feature is deprecated and will be removed in version 9.0.",
       "resolveDuringUpgrade": false,
       "type": "index_settings",
-      "url": "https://www.elastic.co/guide/en/elasticsearch/reference/current/migrating-8.0.html#breaking-changes-8.0",
+      "url": "https://www.elastic.co/guide/en/elasticsearch/reference/master/frozen-indices.html",
     },
     Object {
       "correctiveAction": Object {
-        "blockerForReindexing": "index-closed",
         "excludedActions": Array [],
+        "metadata": Object {
+          "isClosedIndex": true,
+          "isFrozenIndex": false,
+          "isInDataStream": false,
+        },
         "type": "reindex",
       },
       "details": "This index was created using version: 6.8.13",
@@ -177,8 +188,12 @@ Object {
     },
     Object {
       "correctiveAction": Object {
-        "blockerForReindexing": undefined,
         "excludedActions": Array [],
+        "metadata": Object {
+          "isClosedIndex": false,
+          "isFrozenIndex": false,
+          "isInDataStream": false,
+        },
         "transformIds": Array [
           "abc",
         ],
@@ -194,8 +209,12 @@ Object {
     },
     Object {
       "correctiveAction": Object {
-        "blockerForReindexing": undefined,
         "excludedActions": Array [],
+        "metadata": Object {
+          "isClosedIndex": false,
+          "isFrozenIndex": false,
+          "isInDataStream": false,
+        },
         "type": "reindex",
       },
       "details": "This index has version: 7.17.25",
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/get_corrective_actions.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/get_corrective_actions.ts
index 417acacd347f5..839a496af5651 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/get_corrective_actions.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/get_corrective_actions.ts
@@ -5,32 +5,30 @@
  * 2.0.
  */
 
-import { EnrichedDeprecationInfo } from '../../../common/types';
+import type { CorrectiveAction } from '../../../common/types';
+import type { BaseDeprecation } from './migrations';
 
 interface Action {
   action_type: 'remove_settings';
   objects: string[];
 }
 
-interface Actions {
+interface CommonActionMetadata {
   actions?: Action[];
 }
 
-interface MlActionMetadata {
-  actions?: Action[];
+interface MlActionMetadata extends CommonActionMetadata {
   snapshot_id: string;
   job_id: string;
 }
 
-interface IndexActionMetadata {
-  actions?: Action[];
+interface IndexActionMetadata extends CommonActionMetadata {
   reindex_required: boolean;
   transform_ids: string[];
+  is_in_data_stream?: boolean;
 }
 
-interface DataStreamActionMetadata {
-  actions?: Action[];
-
+interface DataStreamActionMetadata extends CommonActionMetadata {
   excludedActions?: Array<'readOnly' | 'reindex'>;
   total_backing_indices: number;
   reindex_required: boolean;
@@ -44,7 +42,7 @@ interface DataStreamActionMetadata {
   ignored_indices_requiring_upgrade_count?: number;
 }
 
-export type EsMetadata = Actions | MlActionMetadata | DataStreamActionMetadata;
+export type EsMetadata = IndexActionMetadata | MlActionMetadata | DataStreamActionMetadata;
 
 // TODO(jloleysens): Replace these regexes once this issue is addressed https://github.com/elastic/elasticsearch/issues/118062
 const ES_INDEX_MESSAGES_REQUIRING_REINDEX = [
@@ -55,26 +53,23 @@ const ES_INDEX_MESSAGES_REQUIRING_REINDEX = [
 export const isFrozenDeprecation = (message: string, indexName?: string): boolean =>
   Boolean(indexName) && message.includes(`Index [${indexName}] is a frozen index`);
 
-export const getCorrectiveAction = (
-  deprecationType: EnrichedDeprecationInfo['type'],
-  message: string,
-  metadata: EsMetadata,
-  indexName?: string
-): EnrichedDeprecationInfo['correctiveAction'] => {
+export const getCorrectiveAction = (deprecation: BaseDeprecation): CorrectiveAction | undefined => {
+  const { index, type, message, metadata } = deprecation;
+
   const indexSettingDeprecation = metadata?.actions?.find(
-    (action) => action.action_type === 'remove_settings' && indexName
+    (action) => action.action_type === 'remove_settings' && index
   );
   const clusterSettingDeprecation = metadata?.actions?.find(
-    (action) => action.action_type === 'remove_settings' && typeof indexName === 'undefined'
+    (action) => action.action_type === 'remove_settings' && typeof index === 'undefined'
   );
   const requiresReindexAction = ES_INDEX_MESSAGES_REQUIRING_REINDEX.some((regexp) =>
     regexp.test(message)
   );
-  const requiresUnfreezeAction = isFrozenDeprecation(message, indexName);
+  const requiresUnfreezeAction = isFrozenDeprecation(message, index);
   const requiresIndexSettingsAction = Boolean(indexSettingDeprecation);
   const requiresClusterSettingsAction = Boolean(clusterSettingDeprecation);
   const requiresMlAction = /[Mm]odel snapshot/.test(message);
-  const requiresDataStreamsAction = deprecationType === 'data_streams';
+  const requiresDataStreamsAction = type === 'data_streams';
 
   if (requiresDataStreamsAction) {
     const {
@@ -114,12 +109,22 @@ export const getCorrectiveAction = (
     return {
       type: 'reindex',
       ...(transformIds?.length ? { transformIds } : {}),
+      metadata: {
+        isClosedIndex: Boolean(deprecation.isClosedIndex),
+        isFrozenIndex: Boolean(deprecation.isFrozenIndex),
+        isInDataStream: Boolean((deprecation.metadata as IndexActionMetadata)?.is_in_data_stream),
+      },
     };
   }
 
   if (requiresUnfreezeAction) {
     return {
       type: 'unfreeze',
+      metadata: {
+        isClosedIndex: Boolean(deprecation.isClosedIndex),
+        isFrozenIndex: Boolean(deprecation.isFrozenIndex),
+        isInDataStream: Boolean((deprecation.metadata as IndexActionMetadata)?.is_in_data_stream),
+      },
     };
   }
 
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/health_indicators.test.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/health_indicators.test.ts
index 3f16d0f9e94ce..e296f82fa8075 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/health_indicators.test.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/health_indicators.test.ts
@@ -5,18 +5,18 @@
  * 2.0.
  */
 
-import { elasticsearchServiceMock, ScopedClusterClientMock } from '@kbn/core/server/mocks';
+import { elasticsearchServiceMock, type ElasticsearchClientMock } from '@kbn/core/server/mocks';
 import { getHealthIndicators } from './health_indicators';
 import * as healthIndicatorsMock from '../__fixtures__/health_indicators';
 
 describe('getHealthIndicators', () => {
-  let esClient: ScopedClusterClientMock;
+  let esClient: ElasticsearchClientMock;
   beforeEach(() => {
-    esClient = elasticsearchServiceMock.createScopedClusterClient();
+    esClient = elasticsearchServiceMock.createScopedClusterClient().asCurrentUser;
   });
 
   it('returns empty array on green indicators', async () => {
-    esClient.asCurrentUser.healthReport.mockResponse({
+    esClient.healthReport.mockResponse({
       cluster_name: 'mock',
       indicators: {
         disk: healthIndicatorsMock.diskIndicatorGreen,
@@ -30,7 +30,7 @@ describe('getHealthIndicators', () => {
   });
 
   it('returns unknown indicators', async () => {
-    esClient.asCurrentUser.healthReport.mockResponse({
+    esClient.healthReport.mockResponse({
       cluster_name: 'mock',
       indicators: {
         disk: healthIndicatorsMock.diskIndicatorUnknown,
@@ -48,7 +48,7 @@ describe('getHealthIndicators', () => {
   });
 
   it('returns unhealthy shards_capacity indicator', async () => {
-    esClient.asCurrentUser.healthReport.mockResponse({
+    esClient.healthReport.mockResponse({
       cluster_name: 'mock',
       indicators: {
         disk: healthIndicatorsMock.diskIndicatorGreen,
@@ -92,7 +92,7 @@ describe('getHealthIndicators', () => {
   });
 
   it('returns unhealthy disk indicator', async () => {
-    esClient.asCurrentUser.healthReport.mockResponse({
+    esClient.healthReport.mockResponse({
       cluster_name: 'mock',
       indicators: {
         disk: healthIndicatorsMock.diskIndicatorRed,
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/health_indicators.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/health_indicators.ts
index 915ccc3ecbb42..fdcaba67c5d9a 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/health_indicators.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/health_indicators.ts
@@ -7,13 +7,13 @@
 
 import { i18n } from '@kbn/i18n';
 import type * as estypes from '@elastic/elasticsearch/lib/api/types';
-import { IScopedClusterClient } from '@kbn/core/server';
-import { EnrichedDeprecationInfo } from '../../../common/types';
+import type { ElasticsearchClient } from '@kbn/core/server';
+import type { EnrichedDeprecationInfo } from '../../../common/types';
 
 export async function getHealthIndicators(
-  dataClient: IScopedClusterClient
+  dataClient: ElasticsearchClient
 ): Promise<EnrichedDeprecationInfo[]> {
-  const healthIndicators = await dataClient.asCurrentUser.healthReport();
+  const healthIndicators = await dataClient.healthReport();
   const isStatusNotGreen = (indicator?: estypes.HealthReportBaseIndicator): boolean => {
     return !!(indicator?.status && indicator?.status !== 'green');
   };
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/index.test.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/index.test.ts
index 5f289bdf72fba..843933ff1258d 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/index.test.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/index.test.ts
@@ -39,13 +39,13 @@ describe('getESUpgradeStatus', () => {
   // @ts-expect-error mock data is too loosely typed
   const deprecationsResponse: estypes.MigrationDeprecationsResponse = _.cloneDeep(fakeDeprecations);
 
-  const esClient = elasticsearchServiceMock.createScopedClusterClient();
+  const esClient = elasticsearchServiceMock.createScopedClusterClient().asCurrentUser;
 
-  esClient.asCurrentUser.healthReport.mockResponse({ cluster_name: 'mock', indicators: {} });
+  esClient.healthReport.mockResponse({ cluster_name: 'mock', indicators: {} });
 
-  esClient.asCurrentUser.migration.deprecations.mockResponse(deprecationsResponse);
+  esClient.migration.deprecations.mockResponse(deprecationsResponse);
 
-  esClient.asCurrentUser.transport.request.mockResolvedValue({
+  esClient.transport.request.mockResolvedValue({
     features: [
       {
         feature_name: 'machine_learning',
@@ -63,11 +63,11 @@ describe('getESUpgradeStatus', () => {
   });
 
   // @ts-expect-error not full interface of response
-  esClient.asCurrentUser.indices.resolveIndex.mockResponse(resolvedIndices);
+  esClient.indices.resolveIndex.mockResponse(resolvedIndices);
 
   it('calls /_migration/deprecations', async () => {
     await getESUpgradeStatus(esClient, { featureSet, dataSourceExclusions });
-    expect(esClient.asCurrentUser.migration.deprecations).toHaveBeenCalled();
+    expect(esClient.migration.deprecations).toHaveBeenCalled();
   });
 
   it('returns the correct shape of data', async () => {
@@ -76,7 +76,7 @@ describe('getESUpgradeStatus', () => {
   });
 
   it('returns totalCriticalDeprecations > 0 when critical issues found', async () => {
-    esClient.asCurrentUser.migration.deprecations.mockResponse({
+    esClient.migration.deprecations.mockResponse({
       // @ts-expect-error not full interface
       cluster_settings: [{ level: 'critical', message: 'Do count me', url: 'https://...' }],
       node_settings: [],
@@ -93,7 +93,7 @@ describe('getESUpgradeStatus', () => {
   });
 
   it('returns totalCriticalDeprecations === 0 when no critical issues found', async () => {
-    esClient.asCurrentUser.migration.deprecations.mockResponse({
+    esClient.migration.deprecations.mockResponse({
       // @ts-expect-error not full interface
       cluster_settings: [{ level: 'warning', message: 'Do not count me', url: 'https://...' }],
       node_settings: [],
@@ -110,7 +110,7 @@ describe('getESUpgradeStatus', () => {
   });
 
   it('filters out system indices returned by upgrade system indices API', async () => {
-    esClient.asCurrentUser.migration.deprecations.mockResponse({
+    esClient.migration.deprecations.mockResponse({
       cluster_settings: [],
       node_settings: [],
       ml_settings: [],
@@ -149,7 +149,7 @@ describe('getESUpgradeStatus', () => {
       ...esMigrationsMock.getMockMlSettingsDeprecations(),
     };
     // @ts-ignore missing property definitions in ES resolve_during_rolling_upgrade and _meta
-    esClient.asCurrentUser.migration.deprecations.mockResponse(mockResponse);
+    esClient.migration.deprecations.mockResponse(mockResponse);
 
     const enabledUpgradeStatus = await getESUpgradeStatus(esClient, {
       featureSet,
@@ -181,7 +181,7 @@ describe('getESUpgradeStatus', () => {
       ...esMigrationsMock.getMockEsDeprecations(),
       ...esMigrationsMock.getMockDataStreamDeprecations(),
     } as MigrationDeprecationsResponse;
-    esClient.asCurrentUser.migration.deprecations.mockResponse(mockResponse);
+    esClient.migration.deprecations.mockResponse(mockResponse);
 
     const enabledUpgradeStatus = await getESUpgradeStatus(esClient, {
       featureSet,
@@ -209,7 +209,7 @@ describe('getESUpgradeStatus', () => {
   });
 
   it('filters out reindex corrective actions if featureSet.reindexCorrectiveActions is set to false', async () => {
-    esClient.asCurrentUser.migration.deprecations.mockResponse({
+    esClient.migration.deprecations.mockResponse({
       cluster_settings: [],
       node_settings: [
         {
@@ -253,7 +253,7 @@ describe('getESUpgradeStatus', () => {
   });
 
   it('filters out old index deprecations enterprise search indices and data streams', async () => {
-    esClient.asCurrentUser.migration.deprecations.mockResponse({
+    esClient.migration.deprecations.mockResponse({
       cluster_settings: [],
       node_settings: [],
       ml_settings: [],
@@ -337,7 +337,7 @@ describe('getESUpgradeStatus', () => {
     });
   });
   it('filters out frozen indices if old index deprecations exist for the same indices', async () => {
-    esClient.asCurrentUser.migration.deprecations.mockResponse({
+    esClient.migration.deprecations.mockResponse({
       cluster_settings: [],
       node_settings: [],
       ml_settings: [],
@@ -369,7 +369,7 @@ describe('getESUpgradeStatus', () => {
     });
 
     // @ts-expect-error not full interface of response
-    esClient.asCurrentUser.indices.resolveIndex.mockResponse(resolvedIndices);
+    esClient.indices.resolveIndex.mockResponse(resolvedIndices);
 
     const upgradeStatus = await getESUpgradeStatus(esClient, {
       featureSet,
@@ -384,7 +384,7 @@ describe('getESUpgradeStatus', () => {
   });
 
   it('returns health indicators', async () => {
-    esClient.asCurrentUser.migration.deprecations.mockResponse({
+    esClient.migration.deprecations.mockResponse({
       cluster_settings: [],
       node_settings: [
         {
@@ -404,7 +404,7 @@ describe('getESUpgradeStatus', () => {
       templates: {},
     });
 
-    esClient.asCurrentUser.healthReport.mockResponse({
+    esClient.healthReport.mockResponse({
       cluster_name: 'mock',
       indicators: {
         disk: healthIndicatorsMock.diskIndicatorGreen,
@@ -450,6 +450,11 @@ describe('getESUpgradeStatus', () => {
         Object {
           "correctiveAction": Object {
             "excludedActions": Array [],
+            "metadata": Object {
+              "isClosedIndex": false,
+              "isFrozenIndex": false,
+              "isInDataStream": false,
+            },
             "type": "reindex",
           },
           "details": "This index was created using version: 6.8.13",
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/index.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/index.ts
index 38864447731d1..bb09c8aa45b34 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/index.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/index.ts
@@ -5,7 +5,7 @@
  * 2.0.
  */
 
-import { IScopedClusterClient } from '@kbn/core/server';
+import { ElasticsearchClient } from '@kbn/core/server';
 import {
   EnrichedDeprecationInfo,
   ESUpgradeStatus,
@@ -19,7 +19,7 @@ import { getHealthIndicators } from './health_indicators';
 import { matchExclusionPattern } from '../data_source_exclusions';
 
 export async function getESUpgradeStatus(
-  dataClient: IScopedClusterClient,
+  dataClient: ElasticsearchClient,
   {
     featureSet,
     dataSourceExclusions,
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/migrations.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/migrations.ts
index c562f6de41407..0e6326e7a77d2 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/migrations.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/migrations.ts
@@ -9,9 +9,9 @@ import type {
   MigrationDeprecationsResponse,
   MigrationDeprecationsDeprecation,
 } from '@elastic/elasticsearch/lib/api/types';
-import { IScopedClusterClient } from '@kbn/core-elasticsearch-server';
-import _ from 'lodash';
-import { EnrichedDeprecationInfo } from '../../../common/types';
+import type { ElasticsearchClient } from '@kbn/core-elasticsearch-server';
+import { omit } from 'lodash';
+import type { CorrectiveAction, EnrichedDeprecationInfo } from '../../../common/types';
 import {
   convertFeaturesToIndicesArray,
   getESSystemIndicesMigrationStatus,
@@ -32,10 +32,24 @@ interface EsDeprecations extends MigrationDeprecationsResponse {
   ilm_policies: Record<string, MigrationDeprecationsDeprecation[]>;
 }
 
-const createBaseMigrationDeprecation = (
+export interface BaseDeprecation {
+  index?: string;
+  type: keyof EsDeprecations;
+  details?: string;
+  message: string;
+  url: string;
+  isCritical: boolean;
+  metadata?: EsMetadata;
+  resolveDuringUpgrade: boolean;
+  // these properties apply to index_settings deprecations only
+  isFrozenIndex?: boolean;
+  isClosedIndex?: boolean;
+}
+
+const createBaseDeprecation = (
   migrationDeprecation: MigrationDeprecationsDeprecation,
   { deprecationType, indexName }: { deprecationType: keyof EsDeprecations; indexName?: string }
-) => {
+): BaseDeprecation => {
   const {
     details,
     message,
@@ -52,16 +66,16 @@ const createBaseMigrationDeprecation = (
     message,
     url,
     isCritical: level === 'critical',
-    metadata,
+    metadata: metadata as EsMetadata,
     resolveDuringUpgrade,
   };
 };
 
 const normalizeEsResponse = (migrationsResponse: EsDeprecations) => {
-  const indexSettingsMigrations = Object.entries(migrationsResponse.index_settings).flatMap(
+  const indexSettingsDeprecations = Object.entries(migrationsResponse.index_settings).flatMap(
     ([indexName, migrationDeprecations]) => {
       return migrationDeprecations.flatMap((migrationDeprecation) =>
-        createBaseMigrationDeprecation(migrationDeprecation, {
+        createBaseDeprecation(migrationDeprecation, {
           indexName,
           deprecationType: 'index_settings',
         })
@@ -69,10 +83,10 @@ const normalizeEsResponse = (migrationsResponse: EsDeprecations) => {
     }
   );
 
-  const dataStreamsMigrations = Object.entries(migrationsResponse.data_streams).flatMap(
+  const dataStreamsDeprecations = Object.entries(migrationsResponse.data_streams).flatMap(
     ([indexName, dataStreamDeprecations]) => {
       return dataStreamDeprecations.flatMap((depractionData) =>
-        createBaseMigrationDeprecation(depractionData, {
+        createBaseDeprecation(depractionData, {
           indexName,
           deprecationType: 'data_streams',
         })
@@ -80,10 +94,10 @@ const normalizeEsResponse = (migrationsResponse: EsDeprecations) => {
     }
   );
 
-  const ilmPoliciesMigrations = Object.entries(migrationsResponse.ilm_policies).flatMap(
+  const ilmPoliciesDeprecations = Object.entries(migrationsResponse.ilm_policies).flatMap(
     ([indexName, ilmPolicyDeprecations]) => {
       return ilmPolicyDeprecations.flatMap((ilmPolicyData) =>
-        createBaseMigrationDeprecation(ilmPolicyData, {
+        createBaseDeprecation(ilmPolicyData, {
           indexName,
           deprecationType: 'ilm_policies',
         })
@@ -91,10 +105,10 @@ const normalizeEsResponse = (migrationsResponse: EsDeprecations) => {
     }
   );
 
-  const templatesMigrations = Object.entries(migrationsResponse.templates).flatMap(
-    ([indexName, templatesDeprecations]) => {
-      return templatesDeprecations.flatMap((templatesDataa) =>
-        createBaseMigrationDeprecation(templatesDataa, {
+  const templatesDeprecations = Object.entries(migrationsResponse.templates).flatMap(
+    ([indexName, templateDeprecations]) => {
+      return templateDeprecations.flatMap((templateData) =>
+        createBaseDeprecation(templateData, {
           indexName,
           deprecationType: 'templates',
         })
@@ -102,129 +116,149 @@ const normalizeEsResponse = (migrationsResponse: EsDeprecations) => {
     }
   );
 
-  const mlSettingsMigrations = migrationsResponse.ml_settings.map((depractionData) =>
-    createBaseMigrationDeprecation(depractionData, { deprecationType: 'ml_settings' })
+  const mlSettingsDeprecations = migrationsResponse.ml_settings.map((depractionData) =>
+    createBaseDeprecation(depractionData, { deprecationType: 'ml_settings' })
   );
-  const nodeSettingsMigrations = migrationsResponse.node_settings.map((depractionData) =>
-    createBaseMigrationDeprecation(depractionData, { deprecationType: 'node_settings' })
+  const nodeSettingsDeprecations = migrationsResponse.node_settings.map((depractionData) =>
+    createBaseDeprecation(depractionData, { deprecationType: 'node_settings' })
   );
 
-  const clusterSettingsMigrations = migrationsResponse.cluster_settings.map((depractionData) =>
-    createBaseMigrationDeprecation(depractionData, { deprecationType: 'cluster_settings' })
+  const clusterSettingsDeprecations = migrationsResponse.cluster_settings.map((depractionData) =>
+    createBaseDeprecation(depractionData, { deprecationType: 'cluster_settings' })
   );
 
   return [
-    ...clusterSettingsMigrations,
-    ...mlSettingsMigrations,
-    ...nodeSettingsMigrations,
-    ...indexSettingsMigrations,
-    ...dataStreamsMigrations,
-    ...ilmPoliciesMigrations,
-    ...templatesMigrations,
+    ...clusterSettingsDeprecations,
+    ...mlSettingsDeprecations,
+    ...nodeSettingsDeprecations,
+    ...indexSettingsDeprecations,
+    ...dataStreamsDeprecations,
+    ...ilmPoliciesDeprecations,
+    ...templatesDeprecations,
   ].flat();
 };
 
+const isKnownDeprecation = (deprecation: BaseDeprecation): boolean => {
+  switch (deprecation.type) {
+    case 'index_settings':
+    case 'cluster_settings':
+    case 'templates':
+    case 'ilm_policies':
+    case 'ml_settings':
+    case 'node_settings':
+    case 'data_streams': {
+      return true;
+    }
+    default: {
+      return false;
+    }
+  }
+};
+
+const enrichIndexSettingsDeprecations = async (
+  esClient: ElasticsearchClient,
+  deprecations: BaseDeprecation[]
+): Promise<void> => {
+  const deprecationsByIndex = new Map<string, BaseDeprecation[]>();
+  const indexSettingsDeprecations = deprecations.filter(
+    (deprecation) => deprecation.type === 'index_settings'
+  );
+
+  // we do a first pass to store all the index deprecations in a Map
+  indexSettingsDeprecations.forEach((deprecation) => {
+    const indexDeprecations = deprecationsByIndex.get(deprecation.index!) ?? [];
+    indexDeprecations.push(deprecation);
+    deprecationsByIndex.set(deprecation.index!, indexDeprecations);
+  });
+
+  // fetch open/closed state for all of the index_settings deprecations indices
+  const indexNames = Array.from(deprecationsByIndex.keys());
+  const indexStates = indexNames.length ? await esIndicesStateCheck(esClient, indexNames) : {};
+
+  // Update some properties for each of the index_settings deprecations
+  indexSettingsDeprecations.forEach((deprecation) => {
+    deprecation.isClosedIndex = indexStates[deprecation.index!] === 'closed';
+
+    // check if a given deprecation is a "frozen index deprecation"
+    const isFrozenIndex = isFrozenDeprecation(deprecation.message, deprecation.index);
+
+    // update all deprecations for the same index
+    if (isFrozenIndex) {
+      deprecationsByIndex
+        .get(deprecation.index!)!
+        .forEach((indexDeprecation) => (indexDeprecation.isFrozenIndex = true));
+    }
+  });
+};
+
+const excludeDeprecation = (
+  deprecation: BaseDeprecation,
+  correctiveAction?: CorrectiveAction
+): boolean => {
+  if (
+    deprecation.type === 'index_settings' &&
+    correctiveAction?.type === 'reindex' &&
+    deprecation.index?.startsWith(ENT_SEARCH_INDEX_PREFIX)
+  ) {
+    return true;
+  } else if (
+    deprecation.type === 'data_streams' &&
+    correctiveAction?.type === 'dataStream' &&
+    correctiveAction.metadata.reindexRequired &&
+    ENT_SEARCH_DATASTREAM_PREFIXES.some((prefix) => deprecation.index?.startsWith(prefix))
+  ) {
+    return true;
+  } else if (
+    deprecation.isCritical &&
+    deprecation.type === 'index_settings' &&
+    deprecation.isFrozenIndex &&
+    correctiveAction?.type === 'reindex'
+  ) {
+    // in this scenario we will already have a "frozen index" deprecation for the same index
+    // we will filter this 'reindex' deprecation out, and let the 'unfreeze' one pass through
+    return true;
+  }
+
+  return false;
+};
+
 export const getEnrichedDeprecations = async (
-  dataClient: IScopedClusterClient
+  esClient: ElasticsearchClient
 ): Promise<EnrichedDeprecationInfo[]> => {
-  const deprecations = (await dataClient.asCurrentUser.migration.deprecations()) as EsDeprecations;
-  const systemIndices = await getESSystemIndicesMigrationStatus(dataClient.asCurrentUser);
+  const esDeprecations = (await esClient.migration.deprecations()) as EsDeprecations;
+  const deprecations = normalizeEsResponse(esDeprecations);
 
+  // Throwing here to avoid allowing upgrades while we have unhandled deprecation types from ES
+  // That might cause the stack to fail to start after upgrade.
+  deprecations.forEach((deprecation) => {
+    if (!isKnownDeprecation(deprecation)) {
+      throw new Error(`Unknown ES deprecation type "${deprecation.type}"`);
+    }
+  });
+
+  // Kibana system indices are handled in a different section of the Upgrade Assistant
+  const systemIndices = await getESSystemIndicesMigrationStatus(esClient);
   const systemIndicesList = convertFeaturesToIndicesArray(systemIndices.features);
+  const filteredDeprecations = deprecations.filter(
+    (deprecation) =>
+      deprecation.type !== 'index_settings' || !systemIndicesList.includes(deprecation.index!)
+  );
 
-  const indexSettingsIndexNames = Object.keys(deprecations.index_settings);
-  const indexSettingsIndexStates = indexSettingsIndexNames.length
-    ? await esIndicesStateCheck(dataClient.asCurrentUser, indexSettingsIndexNames)
-    : {};
-
-  const deprecationsByIndex = new Map<string, EnrichedDeprecationInfo[]>();
-
-  return normalizeEsResponse(deprecations)
-    .filter((deprecation) => {
-      switch (deprecation.type) {
-        case 'index_settings': {
-          if (!deprecation.index) {
-            return false;
-          }
-          // filter out system indices
-          return !systemIndicesList.includes(deprecation.index);
-        }
-        case 'cluster_settings':
-        case 'templates':
-        case 'ilm_policies':
-        case 'ml_settings':
-        case 'node_settings':
-        case 'data_streams': {
-          return true;
-        }
-        default: {
-          // Throwing here to avoid allowing upgrades while we have unhandled deprecation types from ES
-          // That might cause the stack to fail to start after upgrade.
-          throw new Error(`Unknown ES deprecation type "${deprecation.type}"`);
-        }
-      }
-    })
-    .flatMap((deprecation) => {
-      const correctiveAction = getCorrectiveAction(
-        deprecation.type,
-        deprecation.message,
-        deprecation.metadata as EsMetadata,
-        deprecation.index
-      );
+  // Set extra metadata properties for index_settings deprecations
+  await enrichIndexSettingsDeprecations(esClient, filteredDeprecations);
 
-      // Early exclusion of deprecations
-      if (
-        (deprecation.type === 'index_settings' &&
-          correctiveAction?.type === 'reindex' &&
-          deprecation.index?.startsWith(ENT_SEARCH_INDEX_PREFIX)) ||
-        (deprecation.type === 'data_streams' &&
-          correctiveAction?.type === 'dataStream' &&
-          correctiveAction.metadata.reindexRequired &&
-          ENT_SEARCH_DATASTREAM_PREFIXES.some((prefix) => deprecation.index?.startsWith(prefix)))
-      ) {
-        return [];
-      }
-
-      // If we have found deprecation information for index/indices
-      // check whether the index is open or closed.
-      if (deprecation.type === 'index_settings' && correctiveAction?.type === 'reindex') {
-        correctiveAction.blockerForReindexing =
-          indexSettingsIndexStates[deprecation.index!] === 'closed' ? 'index-closed' : undefined;
-      }
-
-      const enrichedDeprecation = {
-        ..._.omit(deprecation, 'metadata'),
-        correctiveAction,
-      };
-
-      if (deprecation.index) {
-        const indexDeprecations = deprecationsByIndex.get(deprecation.index) || [];
-        indexDeprecations.push(enrichedDeprecation);
-        deprecationsByIndex.set(deprecation.index, indexDeprecations);
-      }
-
-      return enrichedDeprecation;
-    })
-    .filter((deprecation) => {
-      if (isFrozenDeprecation(deprecation.message, deprecation.index)) {
-        // frozen indices are created in 7.x, so they are old / incompatible as well
-        // no need to bubble up this deprecation IF THERE IS ANOTHER CRITICAL ONE FOR THE SAME INDEX
-        // in that case, in the critical deprecation we will propose:
-        // - reindexing => the new index will not be frozen
-        // - updating index => the operation will unfreeze the index (see routes/update_index.ts)
-        const indexDeprecations = deprecationsByIndex.get(deprecation.index!);
-        const oldIndexDeprecation: EnrichedDeprecationInfo | undefined = indexDeprecations?.find(
-          (elem) =>
-            elem.type === 'index_settings' &&
-            elem.index === deprecation.index &&
-            elem.correctiveAction?.type === 'reindex' &&
-            elem.isCritical
-        );
-        if (oldIndexDeprecation) {
-          return false;
-        }
-      }
+  // enrich deprecations with the corrective actions, remove metadata
+  return filteredDeprecations.flatMap((deprecation) => {
+    const correctiveAction = getCorrectiveAction(deprecation);
 
-      return true;
-    });
+    // Prevent some deprecations from showing up in the UI
+    if (excludeDeprecation(deprecation, correctiveAction)) {
+      return []; // equivalent of filtering out, thanks to the flatMap
+    }
+
+    return {
+      ...omit(deprecation, 'metadata', 'isFrozenIndex', 'isClosedIndex', 'isInDataStream'),
+      correctiveAction,
+    };
+  });
 };
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_indices_state_check.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_indices_state_check.ts
index deeb9310f9beb..ea18f8c5ce43a 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_indices_state_check.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_indices_state_check.ts
@@ -12,19 +12,16 @@ import { ResolveIndexResponseFromES } from '../../common/types';
 type StatusCheckResult = Record<string, 'open' | 'closed'>;
 
 export const esIndicesStateCheck = async (
-  asCurrentUser: ElasticsearchClient,
+  esClient: ElasticsearchClient,
   indices: string[]
 ): Promise<StatusCheckResult> => {
-  const response = await asCurrentUser.indices.resolveIndex({
+  const response = await esClient.indices.resolveIndex({
     name: '*',
     expand_wildcards: 'all',
   });
 
-  const result: StatusCheckResult = {};
-
-  indices.forEach((index) => {
-    result[index] = getIndexState(index, response as ResolveIndexResponseFromES);
-  });
-
-  return result;
+  return indices.reduce<StatusCheckResult>((acc, index) => {
+    acc[index] = getIndexState(index, response as ResolveIndexResponseFromES);
+    return acc;
+  }, {});
 };
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/reindexing/reindex_service.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/reindexing/reindex_service.ts
index 126af5c398a3f..fc7b95afdd53f 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/lib/reindexing/reindex_service.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/lib/reindexing/reindex_service.ts
@@ -116,9 +116,11 @@ export interface ReindexService {
    * Obtain metadata about the index, including aliases and settings
    * @param indexName
    */
-  getIndexInfo(
-    indexName: string
-  ): Promise<{ aliases: Record<string, IndicesAlias>; settings?: IndicesIndexSettings }>;
+  getIndexInfo(indexName: string): Promise<{
+    aliases: Record<string, IndicesAlias>;
+    settings?: IndicesIndexSettings;
+    isInDataStream: boolean;
+  }>;
 }
 
 export const reindexServiceFactory = (
@@ -356,7 +358,8 @@ export const reindexServiceFactory = (
 
     const aliases = response[indexName]?.aliases ?? {};
     const settings = response[indexName]?.settings?.index ?? {};
-    return { aliases, settings };
+    const isInDataStream = Boolean(response[indexName]?.data_stream);
+    return { aliases, settings, isInDataStream };
   };
 
   const isIndexHidden = async (indexName: string) => {
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/routes/es_deprecations.test.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/routes/es_deprecations.test.ts
index 344e0ed76df25..a95f5ac984778 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/routes/es_deprecations.test.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/routes/es_deprecations.test.ts
@@ -43,6 +43,7 @@ describe('ES deprecations API', () => {
       },
       router: mockRouter,
       lib: { handleEsError },
+      log: { error: jest.fn() },
     };
     registerESDeprecationRoutes(routeDependencies);
   });
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/routes/es_deprecations.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/routes/es_deprecations.ts
index 3f66ca602483f..132d1329faa25 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/routes/es_deprecations.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/routes/es_deprecations.ts
@@ -8,7 +8,7 @@
 import { API_BASE_PATH } from '../../common/constants';
 import { getESUpgradeStatus } from '../lib/es_deprecations_status';
 import { versionCheckHandlerWrapper } from '../lib/es_version_precheck';
-import { RouteDependencies } from '../types';
+import type { RouteDependencies } from '../types';
 import { reindexActionsFactory } from '../lib/reindexing/reindex_actions';
 import { reindexServiceFactory } from '../lib/reindexing';
 
@@ -36,8 +36,10 @@ export function registerESDeprecationRoutes({
           savedObjects: { client: savedObjectsClient },
           elasticsearch: { client },
         } = await core;
-        const status = await getESUpgradeStatus(client, { featureSet, dataSourceExclusions });
-
+        const status = await getESUpgradeStatus(client.asCurrentUser, {
+          featureSet,
+          dataSourceExclusions,
+        });
         const asCurrentUser = client.asCurrentUser;
         const reindexActions = reindexActionsFactory(savedObjectsClient, asCurrentUser);
         const reindexService = reindexServiceFactory(asCurrentUser, reindexActions, log, licensing);
@@ -51,6 +53,7 @@ export function registerESDeprecationRoutes({
           body: status,
         });
       } catch (error) {
+        log.error(error);
         return handleEsError({ error, response });
       }
     })
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/routes/reindex_indices/reindex_indices.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/routes/reindex_indices/reindex_indices.ts
index ec703111df0c8..ae3d66a84ec2c 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/routes/reindex_indices/reindex_indices.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/routes/reindex_indices/reindex_indices.ts
@@ -126,7 +126,7 @@ export function registerReindexIndicesRoutes(
           : [];
 
         const isTruthy = (value?: string | boolean): boolean => value === true || value === 'true';
-        const { aliases, settings } = await reindexService.getIndexInfo(indexName);
+        const { aliases, settings, isInDataStream } = await reindexService.getIndexInfo(indexName);
 
         const body: ReindexStatusResponse = {
           reindexOp: reindexOp ? reindexOp.attributes : undefined,
@@ -138,6 +138,7 @@ export function registerReindexIndicesRoutes(
             aliases: Object.keys(aliases),
             isFrozen: isTruthy(settings?.frozen),
             isReadonly: isTruthy(settings?.verified_read_only),
+            isInDataStream,
           },
         };
 
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/routes/status.test.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/routes/status.test.ts
index ada9c4a16fdfa..4d516e634671e 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/routes/status.test.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/routes/status.test.ts
@@ -118,6 +118,7 @@ describe('Status API', () => {
         lib: { handleEsError },
         current: currentVersion,
         defaultTarget: nextMajor,
+        log: { error: jest.fn() },
       };
 
       registerUpgradeStatusRoute(routeDependencies);
@@ -278,6 +279,7 @@ describe('Status API', () => {
         lib: { handleEsError },
         current: currentVersion,
         defaultTarget: nextMajor,
+        log: { error: jest.fn() },
       };
 
       registerUpgradeStatusRoute(routeDependencies);
diff --git a/x-pack/platform/plugins/private/upgrade_assistant/server/routes/status.ts b/x-pack/platform/plugins/private/upgrade_assistant/server/routes/status.ts
index f76dc24227f29..333725140a643 100644
--- a/x-pack/platform/plugins/private/upgrade_assistant/server/routes/status.ts
+++ b/x-pack/platform/plugins/private/upgrade_assistant/server/routes/status.ts
@@ -23,6 +23,7 @@ export function registerUpgradeStatusRoute({
   lib: { handleEsError },
   current,
   defaultTarget,
+  log,
 }: RouteDependencies) {
   router.get(
     {
@@ -57,7 +58,7 @@ export function registerUpgradeStatusRoute({
         const {
           totalCriticalDeprecations, // critical deprecations
           totalCriticalHealthIssues, // critical health issues
-        } = await getESUpgradeStatus(esClient, { featureSet, dataSourceExclusions });
+        } = await getESUpgradeStatus(esClient.asCurrentUser, { featureSet, dataSourceExclusions });
 
         const getSystemIndicesMigrationStatus = async () => {
           /**
@@ -159,6 +160,7 @@ export function registerUpgradeStatusRoute({
           },
         });
       } catch (error) {
+        log.error(error);
         return handleEsError({ error, response });
       }
     })