Transfer Pricing update quarterly

Summary:

Our company will revise Transfer Price quarterly and make changes if necessary. The issue we face now is the price in Transfer Order and Sales Order are different with Intercompany AR invoice after the TP changed.
The TP has changed after the TO/SO has created but before shipped. After the TP has changed, we start to ship and generate billing. This caused the price different between TO/SO with IC AR invoice as we unable to make changes in TO/SO after creation and it will capture the old TP. IC AR invoice will based on the latest price after the TP changed.