Possibly an odd question I know, but this has come up because of something we have noticed in our mail archiver (Jatheon)
We use alias@domain.com as our default email address, the alias matches the UPN.
Jatheon shows messages addressed to legacy DNs, but it also shows the messages are being sent to the users new DN as a BCC. Is this how Exchange handles emails sent to a legacy DN or alternate email address, i.e. BCC the default address?