diff --git a/build/terraform b/build/terraform
index 3035f1b0da3a..afff5faac6e6 160000
--- a/build/terraform
+++ b/build/terraform
@@ -1 +1 @@
-Subproject commit 3035f1b0da3a1b1a9e8bc6b48213bedce213f0e2
+Subproject commit afff5faac6e6bf72fe2f6717b9c7b3a4c3df6e2a
diff --git a/build/terraform-beta b/build/terraform-beta
index 454e8113d34b..e9c271b85662 160000
--- a/build/terraform-beta
+++ b/build/terraform-beta
@@ -1 +1 @@
-Subproject commit 454e8113d34bf72efdb5a3acafa868838f3643d2
+Subproject commit e9c271b856622d9f8a2c31d45ee1b7f8b81f358e
diff --git a/provider/core.rb b/provider/core.rb
index 882bba208f4a..671c5779b5ad 100644
--- a/provider/core.rb
+++ b/provider/core.rb
@@ -375,6 +375,19 @@ def properties_by_custom_update(properties)
       end
     end
 
+    # Takes a update_url and returns the list of custom updatable properties
+    # that can be updated at that URL. This allows flattened objects
+    # to determine which parent property in the API should be updated with
+    # the contents of the flattened object
+    def custom_update_properties_by_url(properties, update_url)
+      properties_by_custom_update(properties).select do |k, _|
+        k[:update_url] == update_url
+      end.first.last
+      # .first is to grab the element from the select which returns a list
+      # .last is because properties_by_custom_update returns a list of
+      # [{update_url}, [properties,...]] and we only need the 2nd part
+    end
+
     def update_url(resource, url_part)
       return resource.self_link_url if url_part.nil?
 
diff --git a/templates/terraform/resource.erb b/templates/terraform/resource.erb
index 2d33996c6ce0..fcb1345a4970 100644
--- a/templates/terraform/resource.erb
+++ b/templates/terraform/resource.erb
@@ -277,7 +277,7 @@ func resource<%= resource_name -%>Read(d *schema.ResourceData, meta interface{})
     return nil
 }
 
-<% if updatable?(object, properties) -%>
+<% if updatable?(object, object.root_properties) -%>
 func resource<%= resource_name -%>Update(d *schema.ResourceData, meta interface{}) error {
     config := meta.(*Config)
 
@@ -287,8 +287,7 @@ func resource<%= resource_name -%>Update(d *schema.ResourceData, meta interface{
 <%  properties_by_custom_update(object.root_properties).each do |key, props| -%>
 if <%= props.map { |prop| "d.HasChange(\"#{prop.name.underscore}\")" }.join ' || ' -%> {
         obj := make(map[string]interface{})
-<%      props.each do |prop| -%>
-<%      if update_body_properties.include? prop -%>
+<%      custom_update_properties_by_url(properties, key[:update_url]).each do |prop| -%>
         <% schemaPrefix = prop.flatten_object ? "nil" : "d.Get( \"#{prop.name.underscore}\" )" -%>
         <%= prop.api_name -%>Prop, err := expand<%= resource_name -%><%= titlelize_property(prop) -%>(<%= schemaPrefix -%>, d, config)
         if err != nil {
@@ -317,10 +316,6 @@ if <%= props.map { |prop| "d.HasChange(\"#{prop.name.underscore}\")" }.join ' ||
 <%          end -%>
             obj["<%= prop.api_name -%>"] = <%= prop.api_name -%>Prop
         }
-<%        else # if update_body_properties.include? prop -%>
-        <%= prop.api_name -%>Prop := d.Get("<%= prop.name.underscore -%>")
-        obj["<%= prop.api_name -%>"] = <%= prop.api_name -%>Prop
-<%        end # if update_body_properties.include? prop -%>
 <%    end # props.each -%>
 
 <%      if object.mutex -%>