How to credit expense with an AP Credit Memo and link it systematically to a PO/receipt in a Perpetu

The client wishes to maintain perpetual accrual for all their expense receipts since for one reason they don't want to wait till AP invoices are booked before recognizing the project costs incurred.

In which case using perpetual accrual, can anyone think of a way Oracle can credit a PO backed project expense via AP without matching to the PO or receipt and therefore crediting the accrual yet also maintain a link to the purchasing document systematically?

 

My client has a requirement where they receive credit memos to process with POET data.  Their legacy SAP system allows them to process the credit memo as a purchase document matched credit memo without also processing a return receipt and this allows them to credit the expense account which was debited by the receipt, effectively reversing the cost.    This way they can credit expense and still have a reporting link to the PO/receipt to which the credit memo is related.