Originally Posted by
lowfareair
Conspiracy theory - they could have moved the check in desk into that space and expanded each lounge a bit. The 20 seats in the diagram doesn't make a ton of difference. The design motifs are extremely similar between the 2 lounges. My guess is that if the FL becomes consistently overwhelmed, they have the option to close the AC indefinitely and convert the space into a larger, single, FL space. The 'flex space' is essentially the walkway needed to let passengers walk between the two halves without going into the reception area.
Also, a ton more pics at TPG:
https://thepointsguy.com/news/americ...-philadelphia/
This is what happened with the old Envoy lounge (the US Airways Club half was permanently annexed to the Envoy lounge at one point - I don't think they moved any walls, just had the same amenities / food / beverage in both halves of the lounge). With ~20 flagship flights every evening (and by far the smallest FL in the system), my guess is the ~200 seat FL is quickly overwhelmed during the evening push.