Employee given new SSN by IRS. Has anyone had this situation? How did you handle this?

We have received a request from an employee to change their SSN in PS.  We have searched the knowledge base but the only recommendation we found suggested making a fake country to allow us to add the new SSN to the employee's existing record so we don't get a new EmplID.  Has anyone else had this situation come up?  If you have, how did you handle this?  We're thinking it would be cleaner to terminate the current record and hire them all over again with new SSN.  There are too many downstream uses of the SSN in the delivered and