Update mandatory

app/models/case_log.rb

@@ -468,9 +468,19 @@ private
   end
 
   def dynamically_not_required
-    previous_la_known_field = postcode_known? ? %w[previous_la_known] : []
+    not_required = []
-    tshortfall_field = tshortfall_unknown? ? %w[tshortfall] : []
+    not_required << "previous_la_known" if postcode_known?
-    previous_la_known_field + tshortfall_field
+    not_required << "tshortfall" if tshortfall_unknown?
+    not_required << "tenancylength" if tenancylength_optional?
+
+    not_required
+  end
+
+  def tenancylength_optional?
+    return false unless collection_start_year
+    return true if collection_start_year < 2022
+
+    collection_start_year >= 2022 && ![4, 6].include?(tenancy)
   end
 
   def set_derived_fields!

config/forms/2022_2023.json

@@ -1095,10 +1095,13 @@
               },
               "depends_on": [
                 {
-                  "tenancy": 1
+                  "tenancy": 4
                 },
                 {
                   "tenancy": 6
+                },
+                {
+                  "tenancy": 3
                 }
               ]
             },