After entering the lounge you go upstairs via the escalator, turn left and it's about half way down on the lefthand side.

Two weeks ago I met staff members who asked my opinion of it, and had a short conversation where they said they're actively trying to improve the Ultimate experience in AMS. I've no details to share on what the improvements are exactly however it did give me some renewed confidence that, over time, the Ultimate experience in AMS will improve.