Our office manager uses an older external software program for all our accounting and issues tax receipts from that program. At present, we are not using CiviCRM for contributions. We have the external program's Giving ID as a Contact custom field in CiviCRM (called 'Envelope #').
The rest of our staff use CiviCRM for all contact management in their departments, and our website users can update their own CiviCRM contact information directly from their Drupal user account. Lots of addresses could be updated, and our office manager would never know about them.
How can our office manager be notified of any mailing address changes for only people with Envelope #'s? That way, she can change the address(es) in the external software and send the receipts to the correct address.