Does work email replace personal email once candidate is converted to employee from pending worker

Summary:

I have a username generation query, I’m hoping you might be able to help with?

 Lets say we have set username generation set to be email in the system and then hired a worker via recruitment and move to HR .

 will the pending worker use personal email for logging into the system? If yes after conversion of pending worker to employee, once we update the work email will the existing personal email in user account on security console is replaced by work email? OR

Adding work email at the later stage (during conversion), won't change the existing username. However you can update the user name from Manage users.