Hi Mark,
You can create a copy of the sheet,
remove the extension,
then re-own this to the other user,
(see sharing button, transfer ownership)
and reinstall FM using the preferred user.
You'll find the templates as hidden tabs in the sheet, both in the original and the copy so you won't loose or forget anything.
If you don't want to communicate yet another URL of your form you cab retain the one you had but reassign the attached sheet to the new one.
You could also re-own the form to the new user, and then attach it to the copy/new version,
but it's not absolutely necessary.
If you create failsafe triggers,
which make sure there is an address to sent to,
and material/body which meets your req's,
the set FM to run automatically after each form submission AND set the sheet to recalculate each minute - regardless if you have it open or not - so triggers which take longer to calculate will catch-up within a minute (or two).
A little rehearsal this way could also be executed by doing it twice but with another copy so you'll be safe anyway.
Bear in mind it's best to use a functional userid instead of a personal userid to better control the setup in general.
ba...@domain.tld might get another job but servi...@domain.tld won't ;)
Final note:
FM's own failsafe is to not sent records again which already have a sent timestamp...
...which you can delete uf you want the record to be sent again by FM when your triggers are met.
Cheers, Bart