I am presuming that the reason for no UG on the routing via FRA is that there is no longer any space available. There might have been at the time AC made the change, notified you and protected you the day earlier.

I would be "cheesed off" at myself either for not reading my emails and not dealing with the issue on the spot or with myself for not making it part of my secretary's duties to inform me of full day schedule changes.

It is hardly AC's fault that there is no longer space for the UG.