diff --git a/packages/core/src/config/config.test.ts b/packages/core/src/config/config.test.ts
index e92f464fa27..c8fbdc7861f 100644
--- a/packages/core/src/config/config.test.ts
+++ b/packages/core/src/config/config.test.ts
@@ -1,3 +1,4 @@
+
 /**
  * @license
  * Copyright 2026 Google LLC
@@ -2512,6 +2513,80 @@ describe('Config Quota & Preview Model Access', () => {
     });
   });
 
+  describe('getGemini31LaunchedSync', () => {
+  it('should return true if authType is USE_GEMINI', () => {
+    Object.defineProperty(config, 'contentGeneratorConfig', {
+      value: { authType: AuthType.USE_GEMINI },
+      writable: true,
+      configurable: true,
+    });
+
+    expect(config.getGemini31LaunchedSync()).toBe(true);
+    });
+
+   it('should return true if userTier is STANDARD', () => {
+    Object.defineProperty(config, 'contentGeneratorConfig', {
+      value: { authType: AuthType.LOGIN_WITH_GOOGLE },
+      writable: true,
+      configurable: true,
+    });
+
+    vi.mocked(getCodeAssistServer).mockReturnValue({
+      userTier: UserTierId.STANDARD,
+    } as Partial<CodeAssistServer> as CodeAssistServer);
+
+    expect(config.getGemini31LaunchedSync()).toBe(true);
+  });
+
+  it('should return true if experiment flag is true', () => {
+    Object.defineProperty(config, 'contentGeneratorConfig', {
+      value: { authType: AuthType.LOGIN_WITH_GOOGLE },
+      writable: true,
+      configurable: true,
+    });
+
+    vi.mocked(getCodeAssistServer).mockReturnValue({
+      userTier: UserTierId.FREE,
+    } as Partial<CodeAssistServer> as CodeAssistServer);
+
+    Object.defineProperty(config, 'experiments', {
+      value: {
+        flags: {
+          [ExperimentFlags.GEMINI_3_1_PRO_LAUNCHED]: { boolValue: true },
+        },
+      },
+      writable: true,
+      configurable: true,
+    });
+
+    expect(config.getGemini31LaunchedSync()).toBe(true);
+  });
+
+  it('should return false if authType is Google, userTier is FREE, and flag is false', () => {
+    Object.defineProperty(config, 'contentGeneratorConfig', {
+      value: { authType: AuthType.LOGIN_WITH_GOOGLE },
+      writable: true,
+      configurable: true,
+    });
+
+    vi.mocked(getCodeAssistServer).mockReturnValue({
+      userTier: UserTierId.FREE,
+    } as Partial<CodeAssistServer> as CodeAssistServer);
+
+    Object.defineProperty(config, 'experiments', {
+      value: {
+        flags: {
+          [ExperimentFlags.GEMINI_3_1_PRO_LAUNCHED]: { boolValue: false },
+        },
+      },
+      writable: true,
+      configurable: true,
+    });
+
+    expect(config.getGemini31LaunchedSync()).toBe(false);
+  });
+});
+
   describe('isPlanEnabled', () => {
     it('should return false by default', () => {
       const config = new Config(baseParams);
diff --git a/packages/core/src/config/config.ts b/packages/core/src/config/config.ts
index 7297693b8e9..4215d29e657 100644
--- a/packages/core/src/config/config.ts
+++ b/packages/core/src/config/config.ts
@@ -108,10 +108,10 @@ import type { EventEmitter } from 'node:events';
 import { PolicyEngine } from '../policy/policy-engine.js';
 import { ApprovalMode, type PolicyEngineConfig } from '../policy/types.js';
 import { HookSystem } from '../hooks/index.js';
-import type {
+import {
   UserTierId,
-  RetrieveUserQuotaResponse,
-  AdminControlsSettings,
+  type RetrieveUserQuotaResponse,
+  type AdminControlsSettings,
 } from '../code_assist/types.js';
 import type { HierarchicalMemory } from './memory.js';
 import { getCodeAssistServer } from '../code_assist/codeAssist.js';
@@ -2383,6 +2383,12 @@ export class Config {
     ) {
       return true;
     }
+
+    const codeAssistServer = getCodeAssistServer(this);
+    if (codeAssistServer?.userTier === UserTierId.STANDARD) {
+      return true;
+    }
+
     return (
       this.experiments?.flags[ExperimentFlags.GEMINI_3_1_PRO_LAUNCHED]
         ?.boolValue ?? false