diff --git a/app/controllers/schemes_controller.rb b/app/controllers/schemes_controller.rb
index 784ad5f62..7bcdf5694 100644
--- a/app/controllers/schemes_controller.rb
+++ b/app/controllers/schemes_controller.rb
@@ -27,7 +27,11 @@ class SchemesController < ApplicationController
   end
 
   def new_deactivation
-    @scheme_deactivation_period = SchemeDeactivationPeriod.new
+    @scheme_deactivation_period = if @scheme.deactivates_in_more_than_6_months?
+                                    @scheme.open_deactivation || SchemeDeactivationPeriod.new
+                                  else
+                                    SchemeDeactivationPeriod.new
+                                  end
 
     if params[:scheme_deactivation_period].blank?
       render "toggle_active", locals: { action: "deactivate" }
@@ -54,7 +58,7 @@ class SchemesController < ApplicationController
   end
 
   def deactivate
-    if @scheme.scheme_deactivation_periods.create!(deactivation_date: params[:deactivation_date])
+    if @scheme.open_deactivation&.update!(deactivation_date: params[:deactivation_date]) || @scheme.scheme_deactivation_periods.create!(deactivation_date: params[:deactivation_date])
       logs = reset_location_and_scheme_for_logs!
 
       flash[:notice] = deactivate_success_notice
diff --git a/app/models/scheme_deactivation_period.rb b/app/models/scheme_deactivation_period.rb
index 01aafbcb4..e413bb6a9 100644
--- a/app/models/scheme_deactivation_period.rb
+++ b/app/models/scheme_deactivation_period.rb
@@ -4,7 +4,7 @@ class SchemeDeactivationPeriodValidator < ActiveModel::Validator
   def validate(record)
     scheme = record.scheme
     recent_deactivation = scheme.scheme_deactivation_periods.deactivations_without_reactivation.first
-    if recent_deactivation.present?
+    if recent_deactivation.present? && recent_deactivation.deactivation_date <= 6.months.from_now
       validate_reactivation(record, recent_deactivation, scheme)
     else
       validate_deactivation(record, scheme)
diff --git a/app/policies/scheme_policy.rb b/app/policies/scheme_policy.rb
index 58a4efb11..818df8d46 100644
--- a/app/policies/scheme_policy.rb
+++ b/app/policies/scheme_policy.rb
@@ -47,6 +47,7 @@ class SchemePolicy
     confirm_secondary_client_group?
     secondary_client_group?
     new_deactivation?
+    new_reactivation?
     deactivate?
     details?
     support?
diff --git a/spec/requests/schemes_controller_spec.rb b/spec/requests/schemes_controller_spec.rb
index fdd6d64e4..c72fe4397 100644
--- a/spec/requests/schemes_controller_spec.rb
+++ b/spec/requests/schemes_controller_spec.rb
@@ -2001,6 +2001,38 @@ RSpec.describe SchemesController, type: :request do
           end
         end
 
+        context "and there already is a deactivation period" do
+          let(:add_deactivations) { create(:scheme_deactivation_period, deactivation_date: Time.zone.local(2023, 6, 5), reactivation_date: nil, scheme:) }
+
+          before do
+            create(:scheme_deactivation_period, deactivation_date: Time.zone.local(2023, 6, 5), reactivation_date: nil, scheme:)
+            patch "/schemes/#{scheme.id}/deactivate", params:
+          end
+
+          it "updates existing scheme with valid deactivation date and renders scheme page" do
+            follow_redirect!
+            follow_redirect!
+            expect(response).to have_http_status(:ok)
+            expect(page).to have_css(".govuk-notification-banner.govuk-notification-banner--success")
+            scheme.reload
+            expect(scheme.scheme_deactivation_periods.count).to eq(1)
+            expect(scheme.scheme_deactivation_periods.first.deactivation_date).to eq(deactivation_date)
+          end
+
+          it "clears the scheme and scheme answers" do
+            expect(lettings_log.scheme).to eq(scheme)
+            lettings_log.reload
+            expect(lettings_log.scheme).to eq(nil)
+            expect(lettings_log.scheme).to eq(nil)
+          end
+
+          it "marks log as needing attention" do
+            expect(lettings_log.unresolved).to eq(nil)
+            lettings_log.reload
+            expect(lettings_log.unresolved).to eq(true)
+          end
+        end
+
         context "and the users need to be notified" do
           it "sends E-mails to the creators of affected logs with counts" do
             expect {
@@ -2063,6 +2095,35 @@ RSpec.describe SchemesController, type: :request do
           expect(page).to have_content(I18n.t("validations.scheme.toggle_date.invalid"))
         end
       end
+
+      context "when there is an earlier open deactivation" do
+        let(:deactivation_date) { Time.zone.local(2022, 10, 10) }
+        let(:params) { { scheme_deactivation_period: { deactivation_date_type: "other", "deactivation_date(3i)": "8", "deactivation_date(2i)": "9", "deactivation_date(1i)": "2023" } } }
+        let(:add_deactivations) { create(:scheme_deactivation_period, deactivation_date: Time.zone.local(2023, 6, 5), reactivation_date: nil, scheme:) }
+
+        it "redirects to the scheme page and updates the existing deactivation period" do
+          follow_redirect!
+          follow_redirect!
+          follow_redirect!
+          expect(response).to have_http_status(:ok)
+          expect(page).to have_css(".govuk-notification-banner.govuk-notification-banner--success")
+          scheme.reload
+          expect(scheme.scheme_deactivation_periods.count).to eq(1)
+          expect(scheme.scheme_deactivation_periods.first.deactivation_date).to eq(Time.zone.local(2023, 9, 8))
+        end
+      end
+
+      context "when there is a later open deactivation" do
+        let(:deactivation_date) { Time.zone.local(2022, 10, 10) }
+        let(:params) { { scheme_deactivation_period: { deactivation_date_type: "other", "deactivation_date(3i)": "8", "deactivation_date(2i)": "9", "deactivation_date(1i)": "2022" } } }
+        let(:add_deactivations) { create(:scheme_deactivation_period, deactivation_date: Time.zone.local(2023, 6, 5), reactivation_date: nil, scheme:) }
+
+        it "redirects to the confirmation page" do
+          follow_redirect!
+          expect(response).to have_http_status(:ok)
+          expect(page).to have_content("This change will affect 1 logs")
+        end
+      end
     end
   end
 end