I can only comment on inbound for UK passport holders on the way back into the country. There is no matching to a previous photo: you are scanning your passport and having a photo taken of your face simultaneously, whereupon the box fires up on the screen of a guy behind the desk. (You can actually see their screens as you walk past, with all the photos flashing up for them to approve.)
So, you haven't encountered the photo at the gate? Just at security or border? Weird. Pretty sure the flow for me was...
De-plane in Terminal 5, follow signs to Connections, through border control (non-EU), immediately enter automated passport scan/photo machine, re-enter gate-side Terminal 5. Then, at boarding gate, there was another photo machine which appeared to matching that photo with the one taken back at the border check.
And Inverness had none of the above. Just a normal manual check of passport in the security line. Not surprising, given the size of the airport.
I haven't at gate, no. At Newark a couple months ago they had an automated TSA-type check at security which was capturing fingerprints, but I can't quite remember the specifics (feels like the last few months have been either a state of experiencing, or recovering from, jetlag).
I just need to remember that the check-in agents at small Scottish airports don't arrive until 90 min before the first flight of the day. Even if the first flight is 11am. It was pretty weird getting there at 9 and the BA desk was empty with no lights on. I ran into the same thing at Edinburgh a few years ago, but my habit is 2 hours before flights because I've been screwed by long security lines at IAD in the past.
