Sales Credit Memos, Payment terms and due date for payment

Hello all,

does anyone out there know how to get the terms of payment assigned to sales credit memos taken into account when the due date for payment is calculated in the accounting document? (I know this is a bit puzzling as why should one need payment terms for a credit memo)

I have looked at SAP notes 17410 et al..but remain unclear re how 'V' is populated in BSEG-REBZG.