Update Payment Document Number in Auto-generated numbers

We have a regular transaction syncing processes whose document numbers don’t match with the transaction numbers. I’d meant to update the initial number for the payment document number, and instead of checking ‘allow override’, I’d selected and saved ‘update.’

We have a lot of payments, hundreds of thousands. I have two questions:

1. Is this going to update all the document numbers from previous payments, or only those that don’t have document number filled out?
   1. All of our payments have document number filled out.
2. This is taking a really long time, and we’re unable to use the auto-generated numbers features. How long has this taken for other people? And is there a way to stop this process?