diff --git a/app/models/validations/sales/setup_validations.rb b/app/models/validations/sales/setup_validations.rb
index bb99f02ed..d52af8f9b 100644
--- a/app/models/validations/sales/setup_validations.rb
+++ b/app/models/validations/sales/setup_validations.rb
@@ -37,7 +37,7 @@ module Validations::Sales::SetupValidations
     if absorbing_owning_organisation_inactive?(record)
       record.errors.add :saledate, I18n.t("validations.setup.saledate.invalid_absorbing_organisations_saledate",
                                           owning_organisation: record.owning_organisation.name,
-                                          owning_organisation_available_from: record.owning_organisation.created_at.to_formatted_s(:govuk_date))
+                                          owning_organisation_available_from: record.owning_organisation.available_from.to_formatted_s(:govuk_date))
     end
   end
 
@@ -50,10 +50,10 @@ module Validations::Sales::SetupValidations
                                                           owning_organisation: record.owning_organisation.name,
                                                           owning_organisation_merge_date: record.owning_organisation.merge_date.to_formatted_s(:govuk_date),
                                                           owning_absorbing_organisation: record.owning_organisation.absorbing_organisation.name)
-      elsif record.owning_organisation&.absorbed_organisations.present? && record.owning_organisation.created_at.to_date > record.saledate.to_date
+      elsif record.owning_organisation&.absorbed_organisations.present? && record.owning_organisation.available_from.present? && record.owning_organisation.available_from.to_date > record.saledate.to_date
         record.errors.add :owning_organisation_id, I18n.t("validations.setup.owning_organisation.inactive_absorbing_organisation_sales",
                                                           owning_organisation: record.owning_organisation.name,
-                                                          owning_organisation_available_from: record.owning_organisation.created_at.to_formatted_s(:govuk_date))
+                                                          owning_organisation_available_from: record.owning_organisation.available_from.to_formatted_s(:govuk_date))
       end
     end
   end
@@ -104,6 +104,6 @@ private
   end
 
   def absorbing_owning_organisation_inactive?(record)
-    record.owning_organisation&.absorbed_organisations.present? && record.owning_organisation.created_at.to_date > record.saledate.to_date
+    record.owning_organisation&.absorbed_organisations.present? && record.owning_organisation.available_from.present? && record.owning_organisation.available_from.to_date > record.saledate.to_date
   end
 end
diff --git a/app/models/validations/setup_validations.rb b/app/models/validations/setup_validations.rb
index e826c6302..3fd760c30 100644
--- a/app/models/validations/setup_validations.rb
+++ b/app/models/validations/setup_validations.rb
@@ -61,10 +61,10 @@ module Validations::SetupValidations
                                                           owning_organisation: record.owning_organisation.name,
                                                           owning_organisation_merge_date: record.owning_organisation.merge_date.to_formatted_s(:govuk_date),
                                                           owning_absorbing_organisation: record.owning_organisation.absorbing_organisation.name)
-      elsif owning_organisation&.absorbed_organisations.present? && owning_organisation.created_at.to_date > record.startdate.to_date
+      elsif owning_organisation&.absorbed_organisations.present? && owning_organisation.available_from.present? && owning_organisation.available_from.to_date > record.startdate.to_date
         record.errors.add :owning_organisation_id, I18n.t("validations.setup.owning_organisation.inactive_absorbing_organisation",
                                                           owning_organisation: record.owning_organisation.name,
-                                                          owning_organisation_available_from: record.owning_organisation.created_at.to_formatted_s(:govuk_date))
+                                                          owning_organisation_available_from: record.owning_organisation.available_from.to_formatted_s(:govuk_date))
       end
     end
 
@@ -74,10 +74,10 @@ module Validations::SetupValidations
                                                             managing_organisation: record.managing_organisation.name,
                                                             managing_organisation_merge_date: record.managing_organisation.merge_date.to_formatted_s(:govuk_date),
                                                             managing_absorbing_organisation: record.managing_organisation.absorbing_organisation.name)
-      elsif managing_organisation&.absorbed_organisations.present? && managing_organisation.created_at.to_date > record.startdate.to_date
+      elsif managing_organisation&.absorbed_organisations.present? && managing_organisation.available_from.present? && managing_organisation.available_from.to_date > record.startdate.to_date
         record.errors.add :managing_organisation_id, I18n.t("validations.setup.managing_organisation.inactive_absorbing_organisation",
                                                             managing_organisation: record.managing_organisation.name,
-                                                            managing_organisation_available_from: record.managing_organisation.created_at.to_formatted_s(:govuk_date))
+                                                            managing_organisation_available_from: record.managing_organisation.available_from.to_formatted_s(:govuk_date))
       end
     end
   end
@@ -194,20 +194,20 @@ private
     if absorbing_owning_organisation_inactive?(record) && absorbing_managing_organisation_inactive?(record)
       record.errors.add :startdate, I18n.t("validations.setup.startdate.invalid_absorbing_organisations_start_date.different_organisations",
                                            owning_organisation: record.owning_organisation.name,
-                                           owning_organisation_active_from: record.owning_organisation.created_at.to_formatted_s(:govuk_date),
+                                           owning_organisation_active_from: record.owning_organisation.available_from.to_formatted_s(:govuk_date),
                                            managing_organisation: record.managing_organisation.name,
-                                           managing_organisation_active_from: record.managing_organisation.created_at.to_formatted_s(:govuk_date))
+                                           managing_organisation_active_from: record.managing_organisation.available_from.to_formatted_s(:govuk_date))
     else
       if absorbing_owning_organisation_inactive?(record)
         record.errors.add :startdate, I18n.t("validations.setup.startdate.invalid_absorbing_organisations_start_date.owning_organisation",
                                              owning_organisation: record.owning_organisation.name,
-                                             owning_organisation_available_from: record.owning_organisation.created_at.to_formatted_s(:govuk_date))
+                                             owning_organisation_available_from: record.owning_organisation.available_from.to_formatted_s(:govuk_date))
       end
 
       if absorbing_managing_organisation_inactive?(record)
         record.errors.add :startdate, I18n.t("validations.setup.startdate.invalid_absorbing_organisations_start_date.managing_organisation",
                                              managing_organisation: record.managing_organisation.name,
-                                             managing_organisation_available_from: record.managing_organisation.created_at.to_formatted_s(:govuk_date))
+                                             managing_organisation_available_from: record.managing_organisation.available_from.to_formatted_s(:govuk_date))
       end
     end
   end
@@ -221,11 +221,11 @@ private
   end
 
   def absorbing_owning_organisation_inactive?(record)
-    record.owning_organisation&.absorbed_organisations.present? && record.owning_organisation.created_at.to_date > record.startdate.to_date
+    record.owning_organisation&.absorbed_organisations.present? && record.owning_organisation.available_from.present? && record.owning_organisation.available_from.to_date > record.startdate.to_date
   end
 
   def absorbing_managing_organisation_inactive?(record)
-    record.managing_organisation&.absorbed_organisations.present? && record.managing_organisation.created_at.to_date > record.startdate.to_date
+    record.managing_organisation&.absorbed_organisations.present? && record.managing_organisation.available_from.present? && record.managing_organisation.available_from.to_date > record.startdate.to_date
   end
 
   def organisations_belong_to_same_merge?(organisation_a, organisation_b)
diff --git a/db/migrate/20231023142854_add_available_from_to_org.rb b/db/migrate/20231023142854_add_available_from_to_org.rb
new file mode 100644
index 000000000..7cfb4b1aa
--- /dev/null
+++ b/db/migrate/20231023142854_add_available_from_to_org.rb
@@ -0,0 +1,5 @@
+class AddAvailableFromToOrg < ActiveRecord::Migration[7.0]
+  def change
+    add_column :organisations, :available_from, :datetime
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index e353ff9c7..7eda570d1 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.0].define(version: 2023_09_13_093443) do
+ActiveRecord::Schema[7.0].define(version: 2023_10_23_142854) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
@@ -440,6 +440,7 @@ ActiveRecord::Schema[7.0].define(version: 2023_09_13_093443) do
     t.string "old_visible_id"
     t.datetime "merge_date"
     t.bigint "absorbing_organisation_id"
+    t.datetime "available_from"
     t.index ["absorbing_organisation_id"], name: "index_organisations_on_absorbing_organisation_id"
     t.index ["old_visible_id"], name: "index_organisations_on_old_visible_id", unique: true
   end
diff --git a/spec/models/validations/sales/setup_validations_spec.rb b/spec/models/validations/sales/setup_validations_spec.rb
index f7f01eaf7..526024ae3 100644
--- a/spec/models/validations/sales/setup_validations_spec.rb
+++ b/spec/models/validations/sales/setup_validations_spec.rb
@@ -188,7 +188,7 @@ RSpec.describe Validations::Sales::SetupValidations do
 
   describe "#validate_merged_organisations_saledate" do
     let(:record) { build(:sales_log) }
-    let(:absorbing_organisation) { create(:organisation, created_at: Time.zone.local(2023, 2, 1), name: "Absorbing org") }
+    let(:absorbing_organisation) { create(:organisation, created_at: Time.zone.local(2023, 2, 1), available_from: Time.zone.local(2023, 2, 1), name: "Absorbing org") }
     let(:merged_organisation) { create(:organisation, name: "Merged org") }
 
     around do |example|
@@ -218,19 +218,27 @@ RSpec.describe Validations::Sales::SetupValidations do
     end
 
     context "and owning organisation is not yet active during the saledate" do
-      it "does not allow saledate before absorbing organisation has been created" do
+      it "does not allow saledate before absorbing organisation has become available" do
         record.saledate = Time.zone.local(2023, 1, 1)
         record.owning_organisation_id = absorbing_organisation.id
         setup_validator.validate_merged_organisations_saledate(record)
         expect(record.errors["saledate"]).to include(match "Enter a date when the owning organisation was active. Absorbing org became active on 1 February 2023.")
       end
 
-      it "allows saledate after absorbing organisation has been created" do
+      it "allows saledate after absorbing organisation has become available" do
         record.saledate = Time.zone.local(2023, 2, 2)
         record.owning_organisation_id = absorbing_organisation.id
         setup_validator.validate_merged_organisations_saledate(record)
         expect(record.errors["saledate"]).to be_empty
       end
+
+      it "allows saledate if available from is not given" do
+        record.saledate = Time.zone.local(2023, 1, 1)
+        absorbing_organisation.update!(available_from: nil)
+        record.owning_organisation_id = absorbing_organisation.id
+        setup_validator.validate_merged_organisations_saledate(record)
+        expect(record.errors["saledate"]).to be_empty
+      end
     end
   end
 
@@ -238,7 +246,7 @@ RSpec.describe Validations::Sales::SetupValidations do
     let(:record) { build(:sales_log) }
 
     context "when organisations are merged" do
-      let(:absorbing_organisation) { create(:organisation, created_at: Time.zone.local(2023, 2, 1), name: "Absorbing org") }
+      let(:absorbing_organisation) { create(:organisation, created_at: Time.zone.local(2023, 2, 1), available_from: Time.zone.local(2023, 2, 1), name: "Absorbing org") }
       let(:merged_organisation) { create(:organisation, name: "Merged org") }
 
       around do |example|
@@ -265,19 +273,27 @@ RSpec.describe Validations::Sales::SetupValidations do
       end
 
       context "and owning organisation is not yet active during the saledate" do
-        it "does not allow absorbing organisation before it had been created" do
+        it "does not allow absorbing organisation before it has become available" do
           record.saledate = Time.zone.local(2023, 1, 1)
           record.owning_organisation_id = absorbing_organisation.id
           setup_validator.validate_organisation(record)
           expect(record.errors["owning_organisation_id"]).to include(match "The owning organisation must be active on the sale completion date. Absorbing org became active on 1 February 2023.")
         end
 
-        it "allows absorbing organisation after it has been created" do
+        it "allows absorbing organisation after it has become available" do
           record.saledate = Time.zone.local(2023, 2, 2)
           record.owning_organisation_id = absorbing_organisation.id
           setup_validator.validate_organisation(record)
           expect(record.errors["owning_organisation_id"]).to be_empty
         end
+
+        it "allows absorbing organisation if available from is not given" do
+          record.saledate = Time.zone.local(2023, 1, 1)
+          absorbing_organisation.update!(available_from: nil)
+          record.owning_organisation_id = absorbing_organisation.id
+          setup_validator.validate_organisation(record)
+          expect(record.errors["owning_organisation_id"]).to be_empty
+        end
       end
     end
   end
diff --git a/spec/models/validations/setup_validations_spec.rb b/spec/models/validations/setup_validations_spec.rb
index 75b890b24..9228e2ee4 100644
--- a/spec/models/validations/setup_validations_spec.rb
+++ b/spec/models/validations/setup_validations_spec.rb
@@ -136,8 +136,8 @@ RSpec.describe Validations::SetupValidations do
         Timecop.return
       end
 
-      let(:absorbing_organisation) { create(:organisation, created_at: Time.zone.local(2023, 2, 1, 4, 5, 6), name: "Absorbing org") }
-      let(:absorbing_organisation_2) { create(:organisation, created_at: Time.zone.local(2023, 2, 1), name: "Absorbing org 2") }
+      let(:absorbing_organisation) { create(:organisation, created_at: Time.zone.local(2023, 2, 1, 4, 5, 6), available_from: Time.zone.local(2023, 2, 1, 4, 5, 6), name: "Absorbing org") }
+      let(:absorbing_organisation_2) { create(:organisation, created_at: Time.zone.local(2023, 2, 1), available_from: Time.zone.local(2023, 2, 1), name: "Absorbing org 2") }
       let(:merged_organisation) { create(:organisation, name: "Merged org") }
       let(:merged_organisation_2) { create(:organisation, name: "Merged org 2") }
 
@@ -147,14 +147,14 @@ RSpec.describe Validations::SetupValidations do
       end
 
       context "and owning organisation is no longer active" do
-        it "does not allow startate after organisation has been merged" do
+        it "does not allow startdate after organisation has been merged" do
           record.startdate = Time.zone.local(2023, 3, 1)
           record.owning_organisation_id = merged_organisation.id
           setup_validator.validate_startdate_setup(record)
           expect(record.errors["startdate"]).to include(match "Enter a date when the owning organisation was active. Merged org became inactive on 2 February 2023 and was replaced by Absorbing org.")
         end
 
-        it "allows startate before organisation has been merged" do
+        it "allows startdate before organisation has been merged" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.owning_organisation_id = merged_organisation.id
           setup_validator.validate_startdate_setup(record)
@@ -163,30 +163,38 @@ RSpec.describe Validations::SetupValidations do
       end
 
       context "and owning organisation is not yet active during the startdate" do
-        it "does not allow startate before absorbing organisation has been created" do
+        it "does not allow startdate before absorbing organisation has become available" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.owning_organisation_id = absorbing_organisation.id
           setup_validator.validate_startdate_setup(record)
           expect(record.errors["startdate"]).to include(match "Enter a date when the owning organisation was active. Absorbing org became active on 1 February 2023.")
         end
 
-        it "allows startate after absorbing organisation has been created" do
+        it "allows startdate after absorbing organisation has become available" do
           record.startdate = Time.zone.local(2023, 2, 2)
           record.owning_organisation_id = absorbing_organisation.id
           setup_validator.validate_startdate_setup(record)
           expect(record.errors["startdate"]).to be_empty
         end
+
+        it "allows startdate if organisation does not have available from date" do
+          record.startdate = Time.zone.local(2023, 1, 1)
+          absorbing_organisation.update!(available_from: nil)
+          record.owning_organisation_id = absorbing_organisation.id
+          setup_validator.validate_startdate_setup(record)
+          expect(record.errors["startdate"]).to be_empty
+        end
       end
 
       context "and managing organisation is no longer active during the startdate" do
-        it "does not allow startate after organisation has been merged" do
+        it "does not allow startdate after organisation has been merged" do
           record.startdate = Time.zone.local(2023, 3, 1)
           record.managing_organisation_id = merged_organisation.id
           setup_validator.validate_startdate_setup(record)
           expect(record.errors["startdate"]).to include(match "Enter a date when the managing organisation was active. Merged org became inactive on 2 February 2023 and was replaced by Absorbing org.")
         end
 
-        it "allows startate before organisation has been merged" do
+        it "allows startdate before organisation has been merged" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.managing_organisation_id = merged_organisation.id
           setup_validator.validate_startdate_setup(record)
@@ -195,23 +203,31 @@ RSpec.describe Validations::SetupValidations do
       end
 
       context "and managing organisation is not yet active during the startdate" do
-        it "does not allow startate before absorbing organisation has been created" do
+        it "does not allow startdate before absorbing organisation has become available'" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.managing_organisation_id = absorbing_organisation.id
           setup_validator.validate_startdate_setup(record)
           expect(record.errors["startdate"]).to include(match "Enter a date when the managing organisation was active. Absorbing org became active on 1 February 2023.")
         end
 
-        it "allows startate after absorbing organisation has been created" do
+        it "allows startdate after absorbing organisation has become available" do
           record.startdate = Time.zone.local(2023, 2, 2)
           record.managing_organisation_id = absorbing_organisation.id
           setup_validator.validate_startdate_setup(record)
           expect(record.errors["startdate"]).to be_empty
         end
+
+        it "allows startdate if organisation does not have available from date" do
+          record.startdate = Time.zone.local(2023, 1, 1)
+          absorbing_organisation.update!(available_from: nil)
+          record.managing_organisation_id = absorbing_organisation.id
+          setup_validator.validate_startdate_setup(record)
+          expect(record.errors["startdate"]).to be_empty
+        end
       end
 
       context "and owning and managing organisation is no longer active during the startdate" do
-        it "does not allow startate after organisation has been merged" do
+        it "does not allow startdate after organisation has been merged" do
           record.startdate = Time.zone.local(2023, 3, 1)
           record.managing_organisation_id = merged_organisation.id
           record.owning_organisation_id = merged_organisation.id
@@ -219,7 +235,7 @@ RSpec.describe Validations::SetupValidations do
           expect(record.errors["startdate"]).to include(match "Enter a date when the owning and managing organisation was active. Merged org became inactive on 2 February 2023 and was replaced by Absorbing org.")
         end
 
-        it "allows startate before organisation has been merged" do
+        it "allows startdate before organisation has been merged" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.managing_organisation_id = merged_organisation.id
           record.owning_organisation_id = merged_organisation.id
@@ -229,7 +245,7 @@ RSpec.describe Validations::SetupValidations do
       end
 
       context "and owning and managing organisation is not yet active during the startdate" do
-        it "does not allow startate before absorbing organisation has been created" do
+        it "does not allow startdate before absorbing organisation has become available" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.managing_organisation_id = absorbing_organisation.id
           record.owning_organisation_id = absorbing_organisation.id
@@ -237,17 +253,26 @@ RSpec.describe Validations::SetupValidations do
           expect(record.errors["startdate"]).to include(match "Enter a date when the owning and managing organisation was active. Absorbing org became active on 1 February 2023.")
         end
 
-        it "allows startate after absorbing organisation has been created" do
+        it "allows startdate after absorbing organisation has become available" do
           record.startdate = Time.zone.local(2023, 2, 1)
           record.managing_organisation_id = absorbing_organisation.id
           record.owning_organisation_id = absorbing_organisation.id
           setup_validator.validate_startdate_setup(record)
           expect(record.errors["startdate"]).to be_empty
         end
+
+        it "allows startdate if organisation does not have available from date" do
+          record.startdate = Time.zone.local(2023, 1, 1)
+          absorbing_organisation.update!(available_from: nil)
+          record.managing_organisation_id = absorbing_organisation.id
+          record.owning_organisation_id = absorbing_organisation.id
+          setup_validator.validate_startdate_setup(record)
+          expect(record.errors["startdate"]).to be_empty
+        end
       end
 
       context "and owning and managing organisations are no longer active during the startdate" do
-        it "does not allow startate after organisation have been merged" do
+        it "does not allow startdate after organisation have been merged" do
           record.startdate = Time.zone.local(2023, 2, 2)
           record.managing_organisation_id = merged_organisation.id
           record.owning_organisation_id = merged_organisation_2.id
@@ -255,7 +280,7 @@ RSpec.describe Validations::SetupValidations do
           expect(record.errors["startdate"]).to include(match "Enter a date when the owning and managing organisations were active. Merged org 2 and Merged org became inactive on 2 February 2023 and were replaced by Absorbing org.")
         end
 
-        it "allows startate before organisations have been merged" do
+        it "allows startdate before organisations have been merged" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.managing_organisation_id = merged_organisation.id
           record.owning_organisation_id = merged_organisation_2.id
@@ -269,7 +294,7 @@ RSpec.describe Validations::SetupValidations do
           merged_organisation_2.update!(absorbing_organisation: absorbing_organisation_2, merge_date: Time.zone.local(2023, 2, 2))
         end
 
-        it "does not allow startate after organisations have been merged" do
+        it "does not allow startdate after organisations have been merged" do
           record.startdate = Time.zone.local(2023, 3, 1)
           record.managing_organisation_id = merged_organisation.id
           record.owning_organisation_id = merged_organisation_2.id
@@ -277,7 +302,7 @@ RSpec.describe Validations::SetupValidations do
           expect(record.errors["startdate"]).to include(match "Enter a date when the owning and managing organisations were active. Merged org 2 became inactive on 2 February 2023 and was replaced by Absorbing org 2. Merged org became inactive on 2 February 2023 and was replaced by Absorbing org.")
         end
 
-        it "allows startate before organisations have been merged" do
+        it "allows startdate before organisations have been merged" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.managing_organisation_id = merged_organisation.id
           record.owning_organisation_id = merged_organisation_2.id
@@ -291,7 +316,7 @@ RSpec.describe Validations::SetupValidations do
           merged_organisation_2.update!(absorbing_organisation: absorbing_organisation_2, merge_date: Time.zone.local(2023, 2, 2))
         end
 
-        it "does not allow startate before absorbing organisation has been created" do
+        it "does not allow startdate before absorbing organisation has become available" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.managing_organisation_id = absorbing_organisation.id
           record.owning_organisation_id = absorbing_organisation_2.id
@@ -299,13 +324,22 @@ RSpec.describe Validations::SetupValidations do
           expect(record.errors["startdate"]).to include(match "Enter a date when the owning and managing organisations were active. Absorbing org 2 became active on 1 February 2023, and Absorbing org became active on 1 February 2023.")
         end
 
-        it "allows startate after absorbing organisation has been created" do
+        it "allows startdate after absorbing organisation has become available" do
           record.startdate = Time.zone.local(2023, 2, 2)
           record.managing_organisation_id = absorbing_organisation.id
           record.owning_organisation_id = absorbing_organisation.id
           setup_validator.validate_startdate_setup(record)
           expect(record.errors["startdate"]).to be_empty
         end
+
+        it "allows startdate if organisation does not have available from date" do
+          absorbing_organisation.update!(available_from: nil)
+          record.startdate = Time.zone.local(2023, 1, 1)
+          record.managing_organisation_id = absorbing_organisation.id
+          record.owning_organisation_id = absorbing_organisation.id
+          setup_validator.validate_startdate_setup(record)
+          expect(record.errors["startdate"]).to be_empty
+        end
       end
     end
   end
@@ -723,7 +757,7 @@ RSpec.describe Validations::SetupValidations do
     end
 
     context "when organisations are merged" do
-      let(:absorbing_organisation) { create(:organisation, created_at: Time.zone.local(2023, 2, 1, 4, 5, 6), name: "Absorbing org") }
+      let(:absorbing_organisation) { create(:organisation, created_at: Time.zone.local(2023, 2, 1, 4, 5, 6), available_from: Time.zone.local(2023, 2, 1, 4, 5, 6), name: "Absorbing org") }
       let(:merged_organisation) { create(:organisation, name: "Merged org") }
 
       around do |example|
@@ -750,19 +784,27 @@ RSpec.describe Validations::SetupValidations do
       end
 
       context "and owning organisation is not yet active during the startdate" do
-        it "does not allow absorbing organisation before it had been created" do
+        it "does not allow absorbing organisation before it has become available'" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.owning_organisation_id = absorbing_organisation.id
           setup_validator.validate_organisation(record)
           expect(record.errors["owning_organisation_id"]).to include(match "The owning organisation must be active on the tenancy start date. Absorbing org became active on 1 February 2023.")
         end
 
-        it "allows absorbing organisation after it has been created" do
+        it "allows absorbing organisation after it has become available" do
           record.startdate = Time.zone.local(2023, 2, 2)
           record.owning_organisation_id = absorbing_organisation.id
           setup_validator.validate_organisation(record)
           expect(record.errors["owning_organisation_id"]).to be_empty
         end
+
+        it "allows startdate if organisation does not have available from date" do
+          absorbing_organisation.update!(available_from: nil)
+          record.startdate = Time.zone.local(2023, 1, 1)
+          record.owning_organisation_id = absorbing_organisation.id
+          setup_validator.validate_organisation(record)
+          expect(record.errors["owning_organisation_id"]).to be_empty
+        end
       end
 
       context "when managing organisation is no longer active" do
@@ -782,19 +824,27 @@ RSpec.describe Validations::SetupValidations do
       end
 
       context "when managing organisation is not yet active during the startdate" do
-        it "does not allow absorbing organisation before it had been created" do
+        it "does not allow absorbing organisation before it has become available" do
           record.startdate = Time.zone.local(2023, 1, 1)
           record.managing_organisation_id = absorbing_organisation.id
           setup_validator.validate_organisation(record)
           expect(record.errors["managing_organisation_id"]).to include(match "The managing organisation must be active on the tenancy start date. Absorbing org became active on 1 February 2023.")
         end
 
-        it "allows absorbing organisation after it has been created" do
+        it "allows absorbing organisation after it has become available'" do
           record.startdate = Time.zone.local(2023, 2, 2)
           record.managing_organisation_id = absorbing_organisation.id
           setup_validator.validate_organisation(record)
           expect(record.errors["managing_organisation_id"]).to be_empty
         end
+
+        it "allows startdate if organisation does not have available from date" do
+          absorbing_organisation.update!(available_from: nil)
+          record.startdate = Time.zone.local(2023, 1, 1)
+          record.managing_organisation_id = absorbing_organisation.id
+          setup_validator.validate_organisation(record)
+          expect(record.errors["managing_organisation_id"]).to be_empty
+        end
       end
     end
   end