Probably wrong to be irritated with the cabin crew since they have no say / no idea about allocating seats. It's the ground crew responsibility.
If anything you should be more pleased as the inflight crew cared enough to report your irritation to the ground crew and tried to get something done.
perhaps indeed. I'm would (still) write commendations to the inflight crew. but complain about ground ops.
otoh, i guess J was "just" full?
oh well, once the F cabin is open then they need to send staff over anyways. true i would hate to have to bust their lies. btw, did you find out if 1A was a non-rev?