Replace other uses of subsection.id interpolation in copy keys

app/models/form/sales/pages/buyer_interview.rb

@@ -2,7 +2,7 @@ class Form::Sales::Pages::BuyerInterview < ::Form::Page
   def initialize(id, hsh, subsection, joint_purchase:)
     super(id, hsh, subsection)
     @joint_purchase = joint_purchase
-    @copy_key = "sales.#{subsection.id}.noint.#{joint_purchase ? 'joint_purchase' : 'not_joint_purchase'}"
+    @copy_key = "sales.#{subsection.copy_key}.noint.#{joint_purchase ? 'joint_purchase' : 'not_joint_purchase'}"
   end
 
   def questions

app/models/form/sales/pages/privacy_notice.rb

@@ -1,7 +1,7 @@
 class Form::Sales::Pages::PrivacyNotice < ::Form::Page
   def initialize(id, hsh, subsection, joint_purchase:)
     super(id, hsh, subsection)
-    @copy_key = "sales.#{subsection.id}.privacynotice.#{joint_purchase ? 'joint_purchase' : 'not_joint_purchase'}"
+    @copy_key = "sales.#{subsection.copy_key}.privacynotice.#{joint_purchase ? 'joint_purchase' : 'not_joint_purchase'}"
     @joint_purchase = joint_purchase
   end
 

app/models/form/sales/pages/staircase.rb

@@ -3,7 +3,7 @@ class Form::Sales::Pages::Staircase < ::Form::Page
     super
     @id = "staircasing"
     @depends_on = [{ "ownershipsch" => 1 }]
-    @copy_key = "sales.#{subsection.id}.staircasing"
+    @copy_key = "sales.#{subsection.copy_key}.staircasing"
   end
 
   def questions

app/models/form/sales/questions/buyer_interview.rb

@@ -2,7 +2,7 @@ class Form::Sales::Questions::BuyerInterview < ::Form::Question
   def initialize(id, hsh, page, joint_purchase:)
     super(id, hsh, page)
     @id = "noint"
-    @copy_key = "sales.#{subsection.id}.noint.#{joint_purchase ? 'joint_purchase' : 'not_joint_purchase'}"
+    @copy_key = "sales.#{subsection.copy_key}.noint.#{joint_purchase ? 'joint_purchase' : 'not_joint_purchase'}"
     @type = "radio"
     @answer_options = ANSWER_OPTIONS
     @question_number = QUESTION_NUMBER_FROM_YEAR[form.start_date.year] || QUESTION_NUMBER_FROM_YEAR[QUESTION_NUMBER_FROM_YEAR.keys.max]

app/models/form/sales/questions/privacy_notice.rb

@@ -2,7 +2,7 @@ class Form::Sales::Questions::PrivacyNotice < ::Form::Question
   def initialize(id, hsh, page, joint_purchase:)
     super(id, hsh, page)
     @id = "privacynotice"
-    @copy_key = "sales.#{subsection.id}.privacynotice.#{joint_purchase ? 'joint_purchase' : 'not_joint_purchase'}"
+    @copy_key = "sales.#{subsection.copy_key}.privacynotice.#{joint_purchase ? 'joint_purchase' : 'not_joint_purchase'}"
     @type = "checkbox"
     @question_number = QUESTION_NUMBER_FROM_YEAR[form.start_date.year] || QUESTION_NUMBER_FROM_YEAR[QUESTION_NUMBER_FROM_YEAR.keys.max]
     @joint_purchase = joint_purchase