I think being based in the UK (and London in particular), the need for him to spend any real time waiting at a London airport is the most damming bit.

Not for 'security' reasons, nor for 'status' reasons, just because it is a waste of time.

And he would be getting the individual processing away from the masses anyway to avoid the headaches of a crowd for the airport.

So I assume he was in and out in under 30 mins, etc, if at the CCR.