Two years ago I was in First class SFO-LHR and had gone to the GFL. Knew it was 45 minutes until departure and changed into my clothes for the flight, spilt ketchup on myself, cleaned up and headed to the gate to find it empty and hearing the GA to offload my luggage. Informed them I was there and it was 20 min until departure. They said they had been paging me. I said I was in the GFL and my BP had to be scanned to enter the lounge so they knew where I was. Learned International First Class on UA would still get you removed from the flight and am now in the boarding area for international flights 60 min before departure even though most of the time I am waiting around to board with MX delays.