Okay to rename user accounts?

I have just deployed a customised Windows 10 Pro x64 1607 image with six user accounts pre done as part of the SysPrep.

I'd like to use this to reinstall on my sister's PC, too. She only needs four users, but they aren't included in my six (different family).

As there's no difference between any of the accounts apart from one being an administrator, can I rename four of the accounts to save having to create new ones or will I find that the original name's still left somewhere and will pop up at some time in the future and have someone wondering why there's somebody else's name where theirs should be?

I'm aware that the user folders will probably have to be renamed.

Tolqua.

The name may well pop up as setting will be for old name