With the purchasing setup applied, 'Print Previously Applied Documents on Remittance', those documents will show on the payment remittance.

If you issue the remittance, post the payment, and VOID that transaction...

Once you issue the next payment, those previously applied documents do NOT appear on the remittance.

I don't see any reason that those 'previously applied documents' should not go back & always go onto the next remittance issued. Payments are frequently voided because they're never received. If that's the case, the vendor never receives notice on those applied documents.