How is everyone handling Credits that come in an EDI load and are for Matched PO's? Are you selectin

I have created a SR but it's now being considered as working as designed. I'd love to know if anyone has had to customize Voucher Build to deal with credits so that the user preference checkbox does not have to be selected. Our concern with the checkbox is that any voucher that comes in, whether a credit or a debit could then be entered and cause unnecessary match exceptions.