diff --git a/app/models/form_handler.rb b/app/models/form_handler.rb
index 02f3a9d70..9a10dc894 100644
--- a/app/models/form_handler.rb
+++ b/app/models/form_handler.rb
@@ -36,6 +36,10 @@ class FormHandler
     forms["next_lettings"]
   end
 
+  def archived_lettings_form
+    forms["archived_lettings"]
+  end
+
   def current_sales_form
     forms["current_sales"]
   end
@@ -44,6 +48,10 @@ class FormHandler
     forms["previous_sales"]
   end
 
+  def archived_sales_form
+    forms["archived_sales"]
+  end
+
   def next_sales_form
     forms["next_sales"]
   end
diff --git a/app/models/sales_log.rb b/app/models/sales_log.rb
index 3064cba31..d03425ee4 100644
--- a/app/models/sales_log.rb
+++ b/app/models/sales_log.rb
@@ -61,13 +61,14 @@ class SalesLog < Log
              [by_postcode, param_without_spaces, param_without_spaces])
   }
   scope :age1_answered, -> { where.not(age1: nil).or(where(age1_known: [1, 2])) }
+  scope :ecstat1_answered, -> { where.not(ecstat1: nil).or(where("saledate >= ?", Time.zone.local(2025, 4, 1))) }
   scope :duplicate_logs, lambda { |log|
     visible.where(log.slice(*DUPLICATE_LOG_ATTRIBUTES))
     .where.not(id: log.id)
     .where.not(saledate: nil)
     .where.not(sex1: nil)
-    .where.not(ecstat1: nil)
     .where.not(postcode_full: nil)
+    .ecstat1_answered
     .age1_answered
   }
   scope :after_date, ->(date) { where("saledate >= ?", date) }
@@ -77,9 +78,9 @@ class SalesLog < Log
     .group(*DUPLICATE_LOG_ATTRIBUTES)
     .where.not(saledate: nil)
     .where.not(sex1: nil)
-    .where.not(ecstat1: nil)
     .where.not(postcode_full: nil)
     .age1_answered
+    .ecstat1_answered
     .having("COUNT(*) > 1")
 
     if assigned_to_id
diff --git a/spec/factories/sales_log.rb b/spec/factories/sales_log.rb
index 687b042a4..d59a03907 100644
--- a/spec/factories/sales_log.rb
+++ b/spec/factories/sales_log.rb
@@ -33,6 +33,7 @@ FactoryBot.define do
       noint { 2 }
       privacynotice { 1 }
       purchid { rand(999_999_999).to_s }
+      staircase { 1 }
     end
     trait :discounted_ownership_setup_complete do
       saledate_today
@@ -66,6 +67,7 @@ FactoryBot.define do
       postcode_full { "A1 1AA" }
       noint { 2 }
       uprn_known { 0 }
+      staircase { 1 }
     end
     trait :completed do
       purchid { rand(999_999_999).to_s }
diff --git a/spec/features/organisation_spec.rb b/spec/features/organisation_spec.rb
index 15bfecf39..336ae51af 100644
--- a/spec/features/organisation_spec.rb
+++ b/spec/features/organisation_spec.rb
@@ -132,6 +132,7 @@ RSpec.describe "User Features" do
       let!(:other_general_needs_logs) { FactoryBot.create_list(:lettings_log, 4, assigned_to: user, needstype: 1) }
       let!(:other_supported_housing_logs) { FactoryBot.create_list(:lettings_log, 4, assigned_to: user, needstype: 2) }
       let(:number_of_lettings_logs) { LettingsLog.count }
+      let(:previous_year) { FormHandler.instance.previous_lettings_form.start_date.year }
 
       before do
         allow(FormHandler.instance).to receive(:in_crossover_period?).and_return(true)
@@ -204,9 +205,9 @@ RSpec.describe "User Features" do
       end
 
       it "can filter lettings logs by year" do
-        check("years-2022-field")
+        check("years-#{previous_year}-field")
         click_button("Apply filters")
-        expect(page).to have_current_path("/organisations/#{org_id}/lettings-logs?%5Byears%5D[]=&years[]=2022&%5Bstatus%5D[]=&%5Bneedstypes%5D[]=&assigned_to=all&user_text_search=&user=&owning_organisation_select=all&owning_organisation_text_search=&owning_organisation=&managing_organisation_select=all&managing_organisation_text_search=&managing_organisation=")
+        expect(page).to have_current_path("/organisations/#{org_id}/lettings-logs?%5Byears%5D[]=&years[]=#{previous_year}&%5Bstatus%5D[]=&%5Bneedstypes%5D[]=&assigned_to=all&user_text_search=&user=&owning_organisation_select=all&owning_organisation_text_search=&owning_organisation=&managing_organisation_select=all&managing_organisation_text_search=&managing_organisation=")
         expect(page).not_to have_link first_log.id.to_s, href: "/lettings-logs/#{first_log.id}"
       end
 
@@ -226,6 +227,7 @@ RSpec.describe "User Features" do
     context "when viewing sales logs for specific organisation" do
       let(:first_log) { organisation.sales_logs.first }
       let(:number_of_sales_logs) { SalesLog.count }
+      let(:previous_year) { FormHandler.instance.previous_sales_form.start_date.year }
 
       before do
         allow(FormHandler.instance).to receive(:in_crossover_period?).and_return(true)
@@ -254,9 +256,9 @@ RSpec.describe "User Features" do
         organisation.sales_logs.map(&:id).each do |sales_log_id|
           expect(page).to have_link sales_log_id.to_s, href: "/sales-logs/#{sales_log_id}"
         end
-        check("years-2022-field")
+        check("years-#{previous_year}-field")
         click_button("Apply filters")
-        expect(page).to have_current_path("/organisations/#{org_id}/sales-logs?%5Byears%5D[]=&years[]=2022&%5Bstatus%5D[]=&assigned_to=all&user_text_search=&user=&owning_organisation_select=all&owning_organisation_text_search=&owning_organisation=&managing_organisation_select=all&managing_organisation_text_search=&managing_organisation=")
+        expect(page).to have_current_path("/organisations/#{org_id}/sales-logs?%5Byears%5D[]=&years[]=#{previous_year}&%5Bstatus%5D[]=&assigned_to=all&user_text_search=&user=&owning_organisation_select=all&owning_organisation_text_search=&owning_organisation=&managing_organisation_select=all&managing_organisation_text_search=&managing_organisation=")
         expect(page).not_to have_link first_log.id.to_s, href: "/sales-logs/#{first_log.id}"
       end
     end
diff --git a/spec/features/sales_log_spec.rb b/spec/features/sales_log_spec.rb
index 663a4f7ac..c226c6bd3 100644
--- a/spec/features/sales_log_spec.rb
+++ b/spec/features/sales_log_spec.rb
@@ -142,6 +142,7 @@ RSpec.describe "Sales Log Features" do
   context "when downloading logs" do
     let(:user) { create(:user, :support) }
     let(:other_user) { create(:user, organisation: user.organisation) }
+    let(:current_year) { FormHandler.instance.current_sales_form.start_date.year }
 
     context "when I am signed in" do
       before do
@@ -191,7 +192,7 @@ RSpec.describe "Sales Log Features" do
 
       context "when one year filter is selected" do
         before do
-          check("2024 to 2025")
+          check("#{current_year} to #{current_year + 1}")
           click_button("Apply filters")
         end
 
diff --git a/spec/helpers/collection_resources_helper_spec.rb b/spec/helpers/collection_resources_helper_spec.rb
index 05c164fc1..a146e43cc 100644
--- a/spec/helpers/collection_resources_helper_spec.rb
+++ b/spec/helpers/collection_resources_helper_spec.rb
@@ -4,10 +4,18 @@ RSpec.describe CollectionResourcesHelper do
   let(:current_user) { create(:user, :data_coordinator) }
   let(:user) { create(:user, :data_coordinator) }
   let(:storage_service) { instance_double(Storage::S3Service, get_file_metadata: nil) }
+  let(:current_date) { Time.zone.local(2024, 8, 8) }
 
   before do
     allow(Storage::S3Service).to receive(:new).and_return(storage_service)
     allow(storage_service).to receive(:configuration).and_return(OpenStruct.new(bucket_name: "core-test-collection-resources"))
+    Timecop.travel(current_date)
+    Singleton.__init__(FormHandler)
+  end
+
+  after do
+    Timecop.return
+    Singleton.__init__(FormHandler)
   end
 
   describe "when displaying file metadata" do
@@ -34,9 +42,10 @@ RSpec.describe CollectionResourcesHelper do
 
   describe "#editable_collection_resource_years" do
     context "when in crossover period" do
+      let(:current_date) { Time.zone.local(2024, 4, 8) }
+
       before do
         allow(FormHandler.instance).to receive(:in_edit_crossover_period?).and_return(true)
-        allow(Time.zone).to receive(:today).and_return(Time.zone.local(2024, 4, 8))
       end
 
       it "returns previous and current years" do
@@ -50,9 +59,7 @@ RSpec.describe CollectionResourcesHelper do
       end
 
       context "and after 1st January" do
-        before do
-          allow(Time.zone).to receive(:today).and_return(Time.zone.local(2025, 2, 1))
-        end
+        let(:current_date) { Time.zone.local(2025, 2, 1) }
 
         it "returns current and next years" do
           expect(editable_collection_resource_years).to match_array([2024, 2025])
@@ -60,9 +67,7 @@ RSpec.describe CollectionResourcesHelper do
       end
 
       context "and before 1st January" do
-        before do
-          allow(Time.zone).to receive(:today).and_return(Time.zone.local(2024, 12, 1))
-        end
+        let(:current_date) { Time.zone.local(2024, 12, 1) }
 
         it "returns current year" do
           expect(editable_collection_resource_years).to eq([2024])
@@ -73,9 +78,10 @@ RSpec.describe CollectionResourcesHelper do
 
   describe "#displayed_collection_resource_years" do
     context "when in crossover period" do
+      let(:current_date) { Time.zone.local(2024, 4, 8) }
+
       before do
         allow(FormHandler.instance).to receive(:in_edit_crossover_period?).and_return(true)
-        allow(Time.zone).to receive(:today).and_return(Time.zone.local(2024, 4, 8))
       end
 
       it "returns previous and current years" do
@@ -188,9 +194,10 @@ RSpec.describe CollectionResourcesHelper do
     end
 
     context "when next year is editable" do
+      let(:current_date) { Time.zone.local(2025, 1, 1) }
+
       before do
         allow(FormHandler.instance).to receive(:in_edit_crossover_period?).and_return(false)
-        allow(Time.zone).to receive(:today).and_return(Time.zone.local(2025, 1, 1))
       end
 
       it "returns true" do
diff --git a/spec/models/sales_log_derived_fields_spec.rb b/spec/models/sales_log_derived_fields_spec.rb
index ce34c8ca5..8eda0c36f 100644
--- a/spec/models/sales_log_derived_fields_spec.rb
+++ b/spec/models/sales_log_derived_fields_spec.rb
@@ -67,13 +67,13 @@ RSpec.describe SalesLog, type: :model do
     end
 
     it "clears mortgage value if mortgage used is changed from no to don't know" do
-      log = create(:sales_log, :outright_sale_setup_complete, mortgage: 0, mortgageused: 2)
+      log = create(:sales_log, :shared_ownership_setup_complete, stairowned: 100, mortgage: 0, mortgageused: 2)
       log.mortgageused = 3
       expect { log.set_derived_fields! }.to change(log, :mortgage).from(0).to(nil)
     end
 
     it "clears mortgage value if mortgage used is changed from yes to don't know" do
-      log = create(:sales_log, :outright_sale_setup_complete, mortgage: 50_000, mortgageused: 1)
+      log = create(:sales_log, :shared_ownership_setup_complete, staircase: 2, mortgage: 50_000, mortgageused: 1)
       log.mortgageused = 3
       expect { log.set_derived_fields! }.to change(log, :mortgage).from(50_000).to(nil)
     end
@@ -101,30 +101,36 @@ RSpec.describe SalesLog, type: :model do
         expect { log.set_derived_fields! }.to change(log, :deposit).from(0).to(nil)
       end
 
-      it "clears derived deposit when setting mortgage used to yes" do
-        log = create(:sales_log, :outright_sale_setup_complete, value: 123_400, deposit: 123_400, mortgageused: 2)
-        log.mortgageused = 1
-        expect { log.set_derived_fields! }.to change(log, :deposit).from(123_400).to(nil)
+      context "with outright sales log" do
+        before do
+          allow(Time).to receive(:now).and_return(Time.zone.local(2024, 5, 4))
+        end
+
+        it "clears derived deposit when setting mortgage used to yes" do
+          log = create(:sales_log, :outright_sale_setup_complete, value: 123_400, deposit: 123_400, mortgageused: 2)
+          log.mortgageused = 1
+          expect { log.set_derived_fields! }.to change(log, :deposit).from(123_400).to(nil)
+        end
+
+        it "clears that buyer 1 will live in the property if joint purchase is updated" do
+          log = create(:sales_log, :outright_sale_setup_complete, buylivein: 1, jointpur: 2)
+          log.jointpur = 1
+          expect { log.set_derived_fields! }.to change(log, :buy1livein).from(1).to(nil)
+        end
       end
 
       context "when buyers will live in the property" do
         context "and the sale is not a joint purchase" do
           it "derives that buyer 1 will live in the property" do
-            log = build(:sales_log, :outright_sale_setup_complete, buylivein: 1, jointpur: 2)
+            log = build(:sales_log, :shared_ownership_setup_complete, staircase: 2, buylivein: 1, jointpur: 2)
             expect { log.set_derived_fields! }.to change(log, :buy1livein).from(nil).to(1)
           end
 
           it "does not derive a value for whether buyer 2 will live in the property" do
-            log = build(:sales_log, :outright_sale_setup_complete, buylivein: 1, jointpur: 2)
+            log = build(:sales_log, :shared_ownership_setup_complete, staircase: 2, buylivein: 1, jointpur: 2)
             log.set_derived_fields!
             expect(log.buy2livein).to be_nil
           end
-
-          it "clears that buyer 1 will live in the property if joint purchase is updated" do
-            log = create(:sales_log, :outright_sale_setup_complete, buylivein: 1, jointpur: 2)
-            log.jointpur = 1
-            expect { log.set_derived_fields! }.to change(log, :buy1livein).from(1).to(nil)
-          end
         end
 
         context "and the sale is a joint purchase" do
diff --git a/spec/models/sales_log_spec.rb b/spec/models/sales_log_spec.rb
index 0c854c221..20eb0b2a6 100644
--- a/spec/models/sales_log_spec.rb
+++ b/spec/models/sales_log_spec.rb
@@ -281,9 +281,18 @@ RSpec.describe SalesLog, type: :model do
       end
     end
 
-    context "when there is a log with a different ecstat1" do
+    context "when there is a 2024 log with a different ecstat1" do
       let!(:different_ecstat1) { create(:sales_log, :duplicate, ecstat1: 0, owning_organisation: organisation) }
 
+      before do
+        Timecop.freeze(Time.zone.local(2024, 5, 2))
+        Singleton.__init__(FormHandler)
+      end
+
+      after do
+        Timecop.return
+      end
+
       it "does not return a log with a different ecstat1 as a duplicate" do
         expect(described_class.duplicate_logs(log)).not_to include(different_ecstat1)
       end
diff --git a/spec/models/validations/sales/setup_validations_spec.rb b/spec/models/validations/sales/setup_validations_spec.rb
index 659cde23f..45579ca42 100644
--- a/spec/models/validations/sales/setup_validations_spec.rb
+++ b/spec/models/validations/sales/setup_validations_spec.rb
@@ -4,6 +4,8 @@ RSpec.describe Validations::Sales::SetupValidations do
   subject(:setup_validator) { validator_class.new }
 
   let(:validator_class) { Class.new { include Validations::Sales::SetupValidations } }
+  let(:current_year) { FormHandler.instance.current_sales_form.start_date.year }
+  let(:previous_year) { FormHandler.instance.previous_sales_form.start_date.year }
 
   describe "#validate_saledate_collection_year" do
     context "with sales_in_crossover_period == false" do
@@ -68,7 +70,7 @@ RSpec.describe Validations::Sales::SetupValidations do
       end
 
       context "when saledate is in an open previous collection year" do
-        let(:record) { build(:sales_log, saledate: Time.zone.local(2024, 1, 1)) }
+        let(:record) { build(:sales_log, saledate: Time.zone.local(current_year, 1, 1)) }
 
         before do
           allow(FormHandler.instance).to receive(:sales_in_crossover_period?).and_return(true)
@@ -91,12 +93,12 @@ RSpec.describe Validations::Sales::SetupValidations do
         it "adds error" do
           setup_validator.validate_saledate_collection_year(record)
 
-          expect(record.errors[:saledate]).to include("Enter a date within the 2023 to 2024 or 2024 to 2025 collection years, which is between 1st April 2023 and 31st March 2025.")
+          expect(record.errors[:saledate]).to include("Enter a date within the #{previous_year} to #{previous_year + 1} or #{current_year} to #{current_year + 1} collection years, which is between 1st April #{previous_year} and 31st March #{current_year + 1}.")
         end
       end
 
       context "when saledate is after an open collection year" do
-        let(:record) { build(:sales_log, saledate: Time.zone.local(2025, 4, 1)) }
+        let(:record) { build(:sales_log, saledate: Time.zone.local(current_year + 1, 4, 1)) }
 
         before do
           allow(FormHandler.instance).to receive(:sales_in_crossover_period?).and_return(true)
@@ -105,21 +107,17 @@ RSpec.describe Validations::Sales::SetupValidations do
         it "adds error" do
           setup_validator.validate_saledate_collection_year(record)
 
-          expect(record.errors[:saledate]).to include("Enter a date within the 2023 to 2024 or 2024 to 2025 collection years, which is between 1st April 2023 and 31st March 2025.")
+          expect(record.errors[:saledate]).to include("Enter a date within the #{previous_year} to #{previous_year + 1} or #{current_year} to #{current_year + 1} collection years, which is between 1st April #{previous_year} and 31st March #{current_year + 1}.")
         end
       end
 
       context "when current time is after the new logs end date but before edit end date for the previous period" do
         let(:record) { build(:sales_log, saledate: nil) }
 
-        before do
-          allow(Time).to receive(:now).and_return(Time.zone.local(2025, 1, 8))
-        end
-
         it "cannot create new logs for the archived collection year" do
           record.saledate = Time.zone.local(2023, 1, 1)
           setup_validator.validate_saledate_collection_year(record)
-          expect(record.errors["saledate"]).to include(match "Enter a date within the 2023 to 2024 or 2024 to 2025 collection years, which is between 1st April 2023 and 31st March 2025.")
+          expect(record.errors["saledate"]).to include(match "Enter a date within the #{previous_year} to #{previous_year + 1} or #{current_year} to #{current_year + 1} collection years, which is between 1st April #{previous_year} and 31st March #{current_year + 1}.")
         end
 
         it "can edit already created logs for the previous collection year" do
@@ -127,7 +125,7 @@ RSpec.describe Validations::Sales::SetupValidations do
           record.save!(validate: false)
           record.saledate = Time.zone.local(2024, 1, 1)
           setup_validator.validate_saledate_collection_year(record)
-          expect(record.errors["saledate"]).not_to include(match "Enter a date within the 2024 to 2025 collection year, which is between 1st April 2024 and 31st March 2025.")
+          expect(record.errors["saledate"]).not_to include(match "Enter a date within the #{current_year} to #{current_year + 1} collection year, which is between 1st April #{current_year} and 31st March #{current_year + 1}.")
         end
       end