Interesting experience on BA1403 today. I asked to sit in 1D and the checkin staff were very amenable and wrote on my boarding pass 1D as the system wouldn’t let them select it. It was blocked but did not have anyone in it. They didn’t understand why they couldn’t put me in it but said on boarding, I could sit there.

When I got on board, the sole Group 0 passenger was in 1F. Does GGL have the ability to hard block adjacent seats if the cabin isn’t full elsewhere? I am currently a lowly Silver.