So we have support@domain.com and it continually gets added as an additional CC. I think it then causes an additional email notification coming through to me saying “A Ticket Reply came in for Des Quinn” when it was my update 
And then I will need to remember to remove the address from the additional CCs.
I wouldn’t use an actual user with your support email address or there are all sorts of downstream effects that will occur, like the one you are experiencing here. You can still have emails going out from support@, but you don’t really want that being treated as a user within Syncro.
I am not sure where the “being treated as a user” bit comes into this. It is defined as a mailbox and in the SMTP Send settings but not as a user.
Ok I think I misunderstood what you were saying then. To be clear, no users (techs) are in your Syncro instance with the email address of support@ correct?
no none at all. (just filling space)
We also have this with a few email addresses. All are not users and we use them for telephone support (so we have support@ then telcosupport@). They always seem to get added as CC’s.