Why do Credited Purchase Invoices have a different Invoice Number?

Why do Credited Purchase Invoices have a different Invoice Number?

When a Purchase Invoice is Credited, Ostendo simply swaps the Credit and Debit entries.

Example
The Invoice 123456 would be

- Dr Purchases Received Not Invoiced

- Cr Creditors

 The Credit for 123456 would be

- Cr Purchases Received Not Invoiced

- Dr Creditors

 

MYOB 

For MYOB Ostendo appends 100000 to the Invoice number when creating the Credit to segregate the Credit ID from the originating Invoice ID

QuickBooks:

If we did this for Quickbooks however you would get the message "Only one a/r or a/p account allowed per transaction" as the ap account code would appear on both the Debit and Credit sides of the Batch.  Therefore to get around this, if the Accounting Link Style is 'Quickbooks', we add a 'C' to the Credit.  The Accounting Link then creates two batches...one containing the original Invoice Numbers and another containing the one with the added 'C'