We currently do not support enabling the user to change their own email address. The admin user can remove the old email address and add the new one to change the email address.
Go to Manage > Users
Find the old email address and click Remove
Click Invite Users to Account on the top right corner
Add the new email address and click Invite
If the user has Favorites and Saved filters, they would have to manually re-add them back to the new user account.
What would happen to the timesheet data?
Removing a user account (the old email address) will not affect any time data logged into Runn. All the data will still be recorded in the system and are accessible from the Person Dashboard.