Looks like the good people at American Airlines caught on to my plan to sleep, dine and shower at the American Airlines Admirals Club without any intention to fly with them:
Starting November 1, 2019
Boarding passes for same-day travel on American Airlines or partner airlines will be required for entry. Any departing or arriving flight: marketed or operated by American Airlines, marketed and operated by any oneworld® partner carrier, marketed and operated by American Airlines or Alaska Airlines in any combination.
The details can be found here. Previously all you needed to do was show your (hopefully MLA waived) American Airlines Executive card at any Admirals Club and they just let you in without even asking for any boarding pass. You could technically be flying a rival airline, be on a gate pass, or even been an airport employee or USO volunteer, anything to get you past security. Up until November 2019 they would let you in, no questions asked, for some free beer and guac and chips to catch a football game:
We got less than a year to pull off the homeless for a month at the airport challenge! Your best bet now is to get the United Club Card with Chase in order to ensure you have lounge access regardless of the airline you are flying. Now if you are in the terminal with just a gate pass then you have only the USO to go to. American Airlines is now like Delta Sky Clubs, United Club, and Centurion Lounges which all require some boarding pass for entry. No word from Justin Ross Lee on if the fully refundable first class ticket still works:
We still got a year to bum around the AA lounge, but after 01 Nov 2019 we actually got to fly with them! If the $450 annual fee hits on my AA Executive Card, I might have to reconsider if it is worth it!