Yeah, that cryptic 'until August 18' note is intriguing. I wonder what change is coming up. Maybe QR is going to open up their own lounge and start using D gates again.
Anyway for now the flight leaves from E10 or 11. Luckily those are part of the E gates that you don't have to ride a bus to get to.
E premium lounge is just after security. It's also used by BA, Iberia and some AA passengers. I went through security about 3 hours before the flight and it was quiet and quick. I asked the TSA agents and they said it starts getting crowded when it gets under 2 hours before the flight. And keep in mind that TSA Precheck won't apply with just a QR boarding pass.
If you're connecting from an AA domestic flight you can walk airside from Concourse D to E, and avoid any security as long as you got your QR boarding passes at your first departure point.
When you're heading to the lounge you can use either elevator on the sides of the passage just after security, even though only one of them is clearly marked as being for the lounge. Often there will be a bit of a lineup for one elevator while nobody is waiting at the other one.
As was said, the furniture and look of the lounge could use some work. But with BA and maybe QR building new lounges maybe nobody cares to invest in this one. I found the seats near the far side window that overlook the train tracks to be comfortable enough. I think there are still showers here but I haven't used them since the time this was an AA club.
Food is mostly cold stuff. Some sandwiches, raw veggies and dip, some cold cut meats, and maybe a cold pasta dish. AA will contribute their 2 soups of the day.
And the real star of the show is the drink offerings. It's pretty complete and good quality and all self service.
Despite what some signs say, QR does announce when the flight is boarding. So if you drink yourself silly you might stand of chance of being alerted for departure.