Best Practice - Full Time to Contract to Full Time User Status

I'm looking to find out the best practices for an old/new user(s) being setup. We previously had an employee setup with access to Quickbase -- let's say name is Minnie Mouse. The email address associated with the user account is the company email address, minnie.mouse@companyemail.com. This employee/user was a part of our workforce reduction back in March. However, she is now being brought back but as a part-time contract employee which means she will be using her personal email address, minniem@gmail.com. There's a high possibility in the future, however, that she will return to her full-time status.

How can I give her access to Quickbase using her new email address, minniem@gmail.com, so that it doesn't affect anything when she returns to full-time status and has to go back to using her company email, minnie.mouse@companyemail.com? 

To add another layer to this discussion, I have a Task Assigned To user field (displaying the full name) that is on our task forms that have old tasks with her name in them, as these are tasks she was assigned and handled.  Since this field will be used again, I'm not sure how both will display her name and how we will distinguish to end-users which name in the list to select.

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Danaya Bryant
Business Analyst
The van Halem Group
Atlanta GA
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