Refresh cache when option type changed

app/models/spree/option_type_decorator.rb

@@ -0,0 +1,13 @@
+module Spree
+  OptionType.class_eval do
+    has_many :products, through: :product_option_types
+    after_save :refresh_products_cache
+
+
+    private
+
+    def refresh_products_cache
+      products(:reload).each &:refresh_products_cache
+    end
+  end
+end