Originally Posted by
NYC Flyer
Refused entry into a premium class arrivals lounge is not customer service issue warranting compensation, and IMHO, the fact that AS is free to say no does not make the request an appropriate one.
What's inappropriate is an American Airlines employee at the admiral's club departure lounge at LHR telling the OP that they cannot enter with an AS Lounge membership and pretending that they are being super nice by letting the OP in. That's inappropriate and something AS should raise with AA since London is listed on AS's website as a place where members can attend admiral's clubs.
At any rate, I've been in the AA "premium" arrivals lounge in LHR last December 25th, 2018, and if it's any consolation to the OP, the small windowless facility with a few croissants and an employee who had no idea whether the Heathrow Express was running between terminals was not really worth the small trek. I'd never bother going back even if I had the opportunity. The BA arrival's lounge, which I went to a few years ago, is much better. Luckily the Express was running on Christmas day between terminals (even though the rest of the line and the rest of London public transit was shut down), and we were able to get to the Heathrow Hilton, which really has a nicer lounge than the AA "premium" arrivals lounge.