How to handle change in VBS Project Owner user ID or if the Project Owner's credentials not working?

Summary:

There were recent changes to the User IDs ( basically the EmailID) at an organization level, as a result of which all the new user ids are able to access the VBS through the redwood pages. But, the issue is for the existing Project that was created with the with the old credentials ( before change in Email ID).
The UserID/email who was the Project Owner that userid/email is now changed. Say suppose the old email of the project owner was "abc@redwood.com" , now it is changed to say "xyz@redwood.com".

Now when ever a user tries to access the VBS thru Redwood pages, the old project is seen to the new user but they need to be added as a Member. So for this they request Membership, but the Project Owner is not able to approve the request as "abc@redwood.com"" is no more available.