The ISR payment bank is only considered in the ISR process.
The ISR payment bank for the invoice is determined by the Payment bank ISR/QR field in one of the following functions. The system pulls the information from the first entry found.
If you copy an invoice, the existing payment bank is removed and the payment bank determination is repeated when the copied invoice is saved.
Refer to the Swiss legislation guide available at the online help center for a comprehensive overview of setup and usage of this function.