Multiple Margin calculation methods in sales process

Hi all, 

We have a finished good product that is managed using AVC (Average cost).

We have a scenario where we need create a quote or sales order and have the standard cost value for the product load into the Cost field with the margin calculated based upon the STD cost loaded. When the Quote/Order is delivered, we need the Avg cost value to be allocated into the cost field of the delivery line for the product, which should then update the margin again based on the Avg cost value.

On the valuation method screen, we have the Margin Calculation basis set to standard cost which works great for the cost and margin values on the quote and order, but the cost and margin is never updated after the actual stock is allocated and delivered.

Currently using V12 Patch 23

Thank you