Here is where the ORM is a real gem!
The key idea is to keep your class name the same.
After the name of the table is changed in the DB, open the ORM mapper and allow it to update the objects/schema (first option). You'll be notified that there is a change. Jot down the class name that will have a new database table name (e.g. "User"). Remove the offending class. This may not feel like the right thing to do, but at this point no changes have been made yet to your model project. All is well. Next, add the new table from the datasource. Rename the class which will default to the new table name (e.g. "aa_User") to the original class name (e.g. "User"). Save the mapper's changes and the model project will be updated with the database table name change.
The best thing is that ALL of your code that references that business class will be unaffected. Only you and the DBA will have to know that anything even happened.
Hope that helps,
Bill