Based on an older article and the lack of answers when people asked this question, I’m guessing the answer is “They are not”.
When an invoice is created using an installment payment terms type, the invoice is initially created for the full amount, but immediately closed. Subsequent installment invoices are created right afterwards for the individual balances. If I use a “3 equal payments” terms type, the system creates INV001 for the original invoice, closes it, and then creates INV002, INV003, and INV004 for the installments.
I see nothing in the system or in the DAC that gives me a link from INV002, 3, and 4 back to INV001. The usual “ARTran to SOLine” join logic doesn’t exist either. Outside of a description, these three installment invoices seem to be related to nothing else.
