diff --git a/app/jobs/reports/month_helper.rb b/app/jobs/reports/month_helper.rb
index e7a41fb2b04..992d2fb1c6d 100644
--- a/app/jobs/reports/month_helper.rb
+++ b/app/jobs/reports/month_helper.rb
@@ -33,10 +33,5 @@ def months(date_range)
 
       results
     end
-
-    def full_month?(date_range)
-      date_range.begin == date_range.begin.beginning_of_month &&
-        date_range.end == date_range.end.end_of_month
-    end
   end
 end
diff --git a/app/services/db/monthly_sp_auth_count/total_monthly_auth_counts_within_iaa_window.rb b/app/services/db/monthly_sp_auth_count/total_monthly_auth_counts_within_iaa_window.rb
index e7c090d1507..be97f93686c 100644
--- a/app/services/db/monthly_sp_auth_count/total_monthly_auth_counts_within_iaa_window.rb
+++ b/app/services/db/monthly_sp_auth_count/total_monthly_auth_counts_within_iaa_window.rb
@@ -19,32 +19,31 @@ def call(issuer:, iaa:, iaa_start_date:, iaa_end_date:)
 
         iaa_range = (iaa_start_date..iaa_end_date)
 
-        full_months, partial_months = Reports::MonthHelper.months(iaa_range).
-          partition do |month_range|
-            Reports::MonthHelper.full_month?(month_range)
-          end
-
-        # The subqueries create a uniform representation of data:
-        # - full months from monthly_sp_auth_counts
-        # - partial months by aggregating sp_return_logs
+        # Query a month at a time, to keep query time/result size fairly reasonable
         # The results are rows with [user_id, ial, auth_count, year_month]
-        queries = [
-          *full_month_subquery(issuer: issuer, full_months: full_months),
-          *partial_month_subqueries(issuer: issuer, partial_months: partial_months),
-        ]
+        months = Reports::MonthHelper.months(iaa_range)
+        queries = build_queries(issuer: issuer, months: months)
 
         ial_to_year_month_to_users = Hash.new do |ial_h, ial_k|
           ial_h[ial_k] = Hash.new { |ym_h, ym_k| ym_h[ym_k] = Multiset.new }
         end
 
         queries.each do |query|
-          stream_query(query) do |row|
-            user_id = row['user_id']
-            year_month = row['year_month']
-            auth_count = row['auth_count']
-            ial = row['ial']
-
-            ial_to_year_month_to_users[ial][year_month].add(user_id, auth_count)
+          temp_copy = ial_to_year_month_to_users.deep_dup
+
+          with_retries(
+            max_tries: 3,
+            rescue: PG::TRSerializationFailure,
+            handler: proc { ial_to_year_month_to_users = temp_copy },
+          ) do
+            stream_query(query) do |row|
+              user_id = row['user_id']
+              year_month = row['year_month']
+              auth_count = row['auth_count']
+              ial = row['ial']
+
+              ial_to_year_month_to_users[ial][year_month].add(user_id, auth_count)
+            end
           end
         end
 
@@ -81,35 +80,12 @@ def call(issuer:, iaa:, iaa_start_date:, iaa_end_date:)
         rows
       end
 
-      # @return [String]
-      def full_month_subquery(issuer:, full_months:)
-        return if full_months.blank?
-        params = {
-          issuer: issuer,
-          year_months: full_months.map { |r| r.begin.strftime('%Y%m') },
-        }.transform_values { |value| quote(value) }
-
-        format(<<~SQL, params)
-          SELECT
-            monthly_sp_auth_counts.user_id
-          , monthly_sp_auth_counts.year_month
-          , monthly_sp_auth_counts.ial
-          , SUM(monthly_sp_auth_counts.auth_count)::bigint AS auth_count
-          FROM
-            monthly_sp_auth_counts
-          WHERE
-                monthly_sp_auth_counts.issuer = %{issuer}
-            AND monthly_sp_auth_counts.year_month IN %{year_months}
-          GROUP BY
-            monthly_sp_auth_counts.year_month
-          , monthly_sp_auth_counts.ial
-          , monthly_sp_auth_counts.user_id
-        SQL
-      end
-
+      # @param [String] issuer
+      # @param [Array<Range<Date>>] months ranges of dates by month that are included in this iaa,
+      #  the first and last may be partial months
       # @return [Array<String>]
-      def partial_month_subqueries(issuer:, partial_months:)
-        partial_months.map do |month_range|
+      def build_queries(issuer:, months:)
+        months.map do |month_range|
           params = {
             range_start: month_range.begin,
             range_end: month_range.end,
diff --git a/app/services/db/monthly_sp_auth_count/unique_monthly_auth_counts_by_iaa.rb b/app/services/db/monthly_sp_auth_count/unique_monthly_auth_counts_by_iaa.rb
index df505c918e8..968474d40e1 100644
--- a/app/services/db/monthly_sp_auth_count/unique_monthly_auth_counts_by_iaa.rb
+++ b/app/services/db/monthly_sp_auth_count/unique_monthly_auth_counts_by_iaa.rb
@@ -15,32 +15,31 @@ def call(key:, issuers:, start_date:, end_date:)
 
         return [] if !date_range || issuers.blank?
 
-        full_months, partial_months = Reports::MonthHelper.months(date_range).
-          partition do |month_range|
-            Reports::MonthHelper.full_month?(month_range)
-          end
-
-        # The subqueries create a uniform representation of data:
-        # - full months from monthly_sp_auth_counts
-        # - partial months by aggregating sp_return_logs
+        # Query a month at a time, to keep query time/result size fairly reasonable
         # The results are rows with [user_id, ial, auth_count, year_month]
-        queries = [
-          *full_month_subquery(issuers: issuers, full_months: full_months),
-          *partial_month_subqueries(issuers: issuers, partial_months: partial_months),
-        ]
+        months = Reports::MonthHelper.months(date_range)
+        queries = build_queries(issuers: issuers, months: months)
 
         ial_to_year_month_to_users = Hash.new do |ial_h, ial_k|
           ial_h[ial_k] = Hash.new { |ym_h, ym_k| ym_h[ym_k] = Multiset.new }
         end
 
         queries.each do |query|
-          stream_query(query) do |row|
-            user_id = row['user_id']
-            year_month = row['year_month']
-            auth_count = row['auth_count']
-            ial = row['ial']
-
-            ial_to_year_month_to_users[ial][year_month].add(user_id, auth_count)
+          temp_copy = ial_to_year_month_to_users.deep_dup
+
+          with_retries(
+            max_tries: 3,
+            rescue: PG::TRSerializationFailure,
+            handler: proc { ial_to_year_month_to_users = temp_copy },
+          ) do
+            stream_query(query) do |row|
+              user_id = row['user_id']
+              year_month = row['year_month']
+              auth_count = row['auth_count']
+              ial = row['ial']
+
+              ial_to_year_month_to_users[ial][year_month].add(user_id, auth_count)
+            end
           end
         end
 
@@ -76,31 +75,12 @@ def call(key:, issuers:, start_date:, end_date:)
         rows
       end
 
-      # @return [String]
-      def full_month_subquery(issuers:, full_months:)
-        return if full_months.blank?
-        params = {
-          issuers: issuers,
-          year_months: full_months.map { |r| r.begin.strftime('%Y%m') },
-        }.transform_values { |value| quote(value) }
-
-        format(<<~SQL, params)
-          SELECT
-            monthly_sp_auth_counts.user_id
-          , monthly_sp_auth_counts.year_month
-          , monthly_sp_auth_counts.auth_count
-          , monthly_sp_auth_counts.ial
-          FROM
-            monthly_sp_auth_counts
-          WHERE
-                monthly_sp_auth_counts.issuer IN %{issuers}
-            AND monthly_sp_auth_counts.year_month IN %{year_months}
-        SQL
-      end
-
+      # @param [Array<String>] issuers all the issuers for this iaa
+      # @param [Array<Range<Date>>] months ranges of dates by month that are included in this iaa,
+      #  the first and last may be partial months
       # @return [Array<String>]
-      def partial_month_subqueries(issuers:, partial_months:)
-        partial_months.map do |month_range|
+      def build_queries(issuers:, months:)
+        months.map do |month_range|
           params = {
             range_start: month_range.begin,
             range_end: month_range.end,
diff --git a/spec/jobs/reports/agency_invoice_iaa_supplement_report_spec.rb b/spec/jobs/reports/agency_invoice_iaa_supplement_report_spec.rb
index 0af4b89e442..8feac5fac06 100644
--- a/spec/jobs/reports/agency_invoice_iaa_supplement_report_spec.rb
+++ b/spec/jobs/reports/agency_invoice_iaa_supplement_report_spec.rb
@@ -102,24 +102,28 @@
 
         # 1 unique user in month 1 at IAA 2 @ IAL 2
         create(
-          :monthly_sp_auth_count,
+          :sp_return_log,
           user_id: user1.id,
-          auth_count: 1,
           ial: 2,
           issuer: iaa2_sp.issuer,
-          year_month: inside_iaa2.strftime('%Y%m'),
+          requested_at: inside_iaa2,
+          returned_at: inside_iaa2,
+          billable: true,
         )
 
         # 2 users, each 2 auths (1 unique) in month 2 at IAA 2 @ IAL 2
         [user1, user2].each do |user|
-          create(
-            :monthly_sp_auth_count,
-            user_id: user.id,
-            auth_count: 2,
-            ial: 2,
-            issuer: iaa2_sp.issuer,
-            year_month: (inside_iaa2 + 1.month).strftime('%Y%m'),
-          )
+          2.times do
+            create(
+              :sp_return_log,
+              user_id: user.id,
+              ial: 2,
+              issuer: iaa2_sp.issuer,
+              requested_at: inside_iaa2 + 1.month,
+              returned_at: inside_iaa2 + 1.month,
+              billable: true,
+            )
+          end
         end
       end
 
@@ -188,7 +192,7 @@
         let(:iaa2_key) { "#{gtc1.gtc_number}-#{format('%04d', iaa_order2.order_number)}" }
 
         let(:iaa1_range) { Date.new(2020, 4, 15)..Date.new(2021, 4, 14) }
-        let(:iaa2_range) { Date.new(2021, 4, 14)..Date.new(2022, 4, 13) }
+        let(:iaa2_range) { Date.new(2021, 4, 15)..Date.new(2022, 4, 14) }
         it 'counts up costs by issuer + ial, and includes iaa and app_id' do
           results = JSON.parse(report.perform(Time.zone.today), symbolize_names: true)
 
@@ -205,6 +209,18 @@
               iaa_start_date: iaa1_range.begin.to_s,
               iaa_end_date: iaa1_range.end.to_s,
             },
+            {
+              iaa: iaa2_key,
+              ial1_total_auth_count: 0,
+              ial2_total_auth_count: 1,
+              ial1_unique_users: 0,
+              ial2_unique_users: 1,
+              ial1_new_unique_users: 0,
+              ial2_new_unique_users: 1,
+              year_month: inside_iaa2.strftime('%Y%m'),
+              iaa_start_date: iaa2_range.begin.to_s,
+              iaa_end_date: iaa2_range.end.to_s,
+            },
             {
               iaa: iaa2_key,
               ial1_total_auth_count: 0,
@@ -212,7 +228,7 @@
               ial1_unique_users: 0,
               ial2_unique_users: 2,
               ial1_new_unique_users: 0,
-              ial2_new_unique_users: 2,
+              ial2_new_unique_users: 1,
               year_month: (inside_iaa2 + 1.month).strftime('%Y%m'),
               iaa_start_date: iaa2_range.begin.to_s,
               iaa_end_date: iaa2_range.end.to_s,
diff --git a/spec/jobs/reports/agency_invoice_issuer_supplement_report_spec.rb b/spec/jobs/reports/agency_invoice_issuer_supplement_report_spec.rb
index 3c3408ab553..ff602ace3c4 100644
--- a/spec/jobs/reports/agency_invoice_issuer_supplement_report_spec.rb
+++ b/spec/jobs/reports/agency_invoice_issuer_supplement_report_spec.rb
@@ -21,22 +21,28 @@
       end
 
       before do
-        create(
-          :monthly_sp_auth_count,
-          user: user,
-          service_provider: sp,
-          ial: 1,
-          auth_count: 11,
-          year_month: iaa_range.begin.strftime('%Y%m'),
-        )
-        create(
-          :monthly_sp_auth_count,
-          user: user,
-          service_provider: sp,
-          ial: 2,
-          auth_count: 22,
-          year_month: iaa_range.begin.strftime('%Y%m'),
-        )
+        3.times do
+          create(
+            :sp_return_log,
+            user: user,
+            service_provider: sp,
+            ial: 1,
+            requested_at: iaa_range.begin + 1.day,
+            returned_at: iaa_range.begin + 1.day,
+            billable: true,
+          )
+        end
+        4.times do
+          create(
+            :sp_return_log,
+            user: user,
+            service_provider: sp,
+            ial: 2,
+            requested_at: iaa_range.begin + 1.day,
+            returned_at: iaa_range.begin + 1.day,
+            billable: true,
+          )
+        end
       end
 
       it 'totals up auth counts within IAA window by month' do
@@ -50,8 +56,8 @@
               iaa_start_date: '2021-01-01',
               iaa_end_date: '2021-12-31',
               year_month: '202101',
-              ial1_total_auth_count: 11,
-              ial2_total_auth_count: 22,
+              ial1_total_auth_count: 3,
+              ial2_total_auth_count: 4,
               ial1_unique_users: 1,
               ial2_unique_users: 1,
             },
diff --git a/spec/jobs/reports/combined_invoice_supplement_report_spec.rb b/spec/jobs/reports/combined_invoice_supplement_report_spec.rb
index e95582d36b7..9f7ab9ea9e7 100644
--- a/spec/jobs/reports/combined_invoice_supplement_report_spec.rb
+++ b/spec/jobs/reports/combined_invoice_supplement_report_spec.rb
@@ -112,22 +112,24 @@
 
         # 1 unique user in month 1 at IAA 2 sp 1 @ IAL 2
         create(
-          :monthly_sp_auth_count,
+          :sp_return_log,
           user_id: user1.id,
-          auth_count: 1,
           ial: 2,
           issuer: iaa2_sp1.issuer,
-          year_month: inside_iaa2.strftime('%Y%m'),
+          requested_at: inside_iaa2,
+          returned_at: inside_iaa2,
+          billable: true,
         )
 
         # 1 unique user in month 1 at IAA 2 sp 2 @ IAL 2
         create(
-          :monthly_sp_auth_count,
+          :sp_return_log,
           user_id: user2.id,
-          auth_count: 1,
           ial: 2,
           issuer: iaa2_sp2.issuer,
-          year_month: inside_iaa2.strftime('%Y%m'),
+          requested_at: inside_iaa2,
+          returned_at: inside_iaa2,
+          billable: true,
         )
       end
 
diff --git a/spec/jobs/reports/month_helper_spec.rb b/spec/jobs/reports/month_helper_spec.rb
index c3c46f24eb0..c8c12571451 100644
--- a/spec/jobs/reports/month_helper_spec.rb
+++ b/spec/jobs/reports/month_helper_spec.rb
@@ -14,14 +14,4 @@
       )
     end
   end
-
-  describe '.full_month?' do
-    it 'is true when the range is a full month' do
-      expect(full_month?(Date.new(2021, 1, 1)..Date.new(2021, 1, 31))).to eq(true)
-    end
-
-    it 'is false when the range is not a full month' do
-      expect(full_month?(Date.new(2021, 1, 2)..Date.new(2021, 1, 30))).to eq(false)
-    end
-  end
 end
diff --git a/spec/services/db/monthly_sp_auth_count/total_monthly_auth_counts_within_iaa_window_spec.rb b/spec/services/db/monthly_sp_auth_count/total_monthly_auth_counts_within_iaa_window_spec.rb
index e73cdde3894..572c060f9e2 100644
--- a/spec/services/db/monthly_sp_auth_count/total_monthly_auth_counts_within_iaa_window_spec.rb
+++ b/spec/services/db/monthly_sp_auth_count/total_monthly_auth_counts_within_iaa_window_spec.rb
@@ -36,7 +36,7 @@
 
     context 'with data' do
       let(:partial_month_date) { iaa_range.begin + 1.day }
-      let(:full_month_date) { (iaa_range.begin + 1.month).beginning_of_month }
+      let(:full_month_date) { iaa_range.begin + 1.month }
       let(:user) { create(:user) }
 
       before do
@@ -65,17 +65,20 @@
         )
 
         # 11 IAL 1 auths during full month
-        create(
-          :monthly_sp_auth_count,
-          user: user,
-          service_provider: service_provider,
-          ial: 1,
-          year_month: full_month_date.strftime('%Y%m'),
-          auth_count: 11,
-        )
+        11.times do
+          create(
+            :sp_return_log,
+            user: user,
+            service_provider: service_provider,
+            ial: 1,
+            requested_at: full_month_date,
+            returned_at: full_month_date,
+            billable: true,
+          )
+        end
       end
 
-      it 'counts and uniqes auths across sp_return_logs and monthly_sp_auth_counts' do
+      it 'counts and uniques auths' do
         rows = [
           {
             year_month: partial_month_date.strftime('%Y%m'),
@@ -108,7 +111,7 @@
     context 'with only partial months' do
       let(:iaa_range) { Date.new(2021, 1, 15)..Date.new(2021, 1, 17) }
 
-      it 'counts auths across sp_return_logs and monthly_sp_auth_counts' do
+      it 'counts and uniques auths' do
         expect(result).to match_array([])
       end
     end
diff --git a/spec/services/db/monthly_sp_auth_count/unique_monthly_auth_counts_by_iaa_spec.rb b/spec/services/db/monthly_sp_auth_count/unique_monthly_auth_counts_by_iaa_spec.rb
index cb20ee443a0..adcbc987ff7 100644
--- a/spec/services/db/monthly_sp_auth_count/unique_monthly_auth_counts_by_iaa_spec.rb
+++ b/spec/services/db/monthly_sp_auth_count/unique_monthly_auth_counts_by_iaa_spec.rb
@@ -90,26 +90,32 @@
 
         # 1 old user + 1 new user in whole month @ IAL 1
         [user1, user2].each do |user|
-          create(
-            :monthly_sp_auth_count,
-            user_id: user.id,
-            auth_count: 10,
-            ial: 1,
-            issuer: issuer1,
-            year_month: inside_whole_month.strftime('%Y%m'),
-          )
+          10.times do
+            create(
+              :sp_return_log,
+              user_id: user.id,
+              ial: 1,
+              issuer: issuer1,
+              requested_at: inside_whole_month,
+              returned_at: inside_whole_month,
+              billable: true,
+            )
+          end
         end
 
         # 2 old user + 1 new user in whole month @ IAL 2
         [user1, user2, user3].each do |user|
-          create(
-            :monthly_sp_auth_count,
-            user_id: user.id,
-            auth_count: 100,
-            ial: 2,
-            issuer: issuer2,
-            year_month: inside_whole_month.strftime('%Y%m'),
-          )
+          7.times do
+            create(
+              :sp_return_log,
+              user_id: user.id,
+              ial: 2,
+              issuer: issuer2,
+              requested_at: inside_whole_month,
+              returned_at: inside_whole_month,
+              billable: true,
+            )
+          end
         end
       end
 
@@ -151,7 +157,7 @@
             year_month: '202010',
             iaa_start_date: iaa_range.begin.to_s,
             iaa_end_date: iaa_range.end.to_s,
-            total_auth_count: 300,
+            total_auth_count: 21,
             unique_users: 3,
             new_unique_users: 1,
           },