Appreciate if someone can explain.

I noticed the payment term for a purchase order is captured in the purchase order header (tdpur040.cpay). This is defaulted from the supplier master data (tccom020.cpay).

When the invoice for the purchase receipt is created using session tfacp1110s000, again the defaulted payment term for the invoice is from supplier master data. I can understand this as when the invoice is just created (without matching to the purchase receipt), no purchase order information is make known to the invoice. So, the payment term must be defaulted from supplier master and not purchase order.

My problem is clear when consider this case:
Buyer created a purchase order with the payment term change from 30 days (as maintained in the supplier master data) to 60 days. When Finance department create the invoice for this purchase receipt, beside checking the Purchase order or the invoice from supplier, how do the AP staff know the payment term for this invoice is 60 days instead of 30 days ?

Relying on the supplier's invoice for the payment term information is not right as supplier can simply print any payment term in their invoice and we got no control over it.

Thanks