in many cases the receiver (warehouse) does not know to which PO a item should be received they are waiting for response from purchasing (buyer) which delays receiving. Best option would be if they can create a blank receive without a PO and the buyer would attached the PO later, similar to adding bills to receipts.

To clarify we are not looking to change the receipt quantity we just want to be able to attach a PO or multiple PO's after the receipt is completed. So the receiver will be able to do received with out PO and the buyer will attach his po's at a later time.