Make "Automatic Credit Use" as an option on Clientside
Under general settings on admin side there was this option:
"Automatic Credit Use: Tick to automatically apply available credit from a users credit balance to recurring invoices upon creation."
This option have pro and contra. I would prefer an option on client side where he choose the variant itself.
It´s customer friendly when client credit was automatically added to open invoices on my opinion, but there are also customers who are writing, that it is not ok and that he want to decide what happens to his credit.
Both side has right. So the best solution should be an option on client side.