How to disallow of manual allocation of non reserved items during transact move order

Hi Guys,

Just migrating from 11i directly to 12.2.4.

In 11i; For orders, we normally 'pick release', we goto 'transact move orders' in Inventory, manually allocate items to lots (this is our major requirement), and transact (to go further ahead to ship confirm)

In R12, we are being forced to auto allocate our stock in 'transact move orders screen' which is what we do not want.

Went through a Doc ID 837647.1, where we can reserve the the lots we require, and goto transact.

But here lies our problem :

If we have an order of 100, but we want to ship only 80 of it now. I reserve 80items (to various lots). when i goto 'transact move orders screen' , i will need to press the allocate button; which auto allocates rest of the 20 items to a random locator (based on picking rules setup).