We have meeting rooms configured to process external invitations, but have a delegations list that only includes internal staff + a few specific externals. For any external meeting organizer that is not on the delegates list, they can send a meeting invite to an internal employee who forwards it to the room and the room accepts and all is well. UNLESS - if the external organizer sends a meeting update (adds/edits agenda, etc), when the change arrives in the rooms inbox, it is treated as a new invite and tries to replace the existing accepted meeting and gets declined as a result since it was forwarded from internal. How do we get past this and get Exchange to recognize changes to existing approved external meetings? Opening up the delegate list is not a viable option for us.