Could be a FAM, or not. Middle aged guy in jeans and a t-shirt. He was working 2 phones prior to departure and seems to now be watching a movie. I asked him if him if he’d just gotten the seat assignment recently and he said he’d “always”had it. I asked about it at the gate and they said first was oversold by one.
A FAM isn't going to identify himself. A sensible gate agent isn't going to confirm your suspicion they added a FAM.