It's amazing just how busy and delay-prone STN can be. On Tuesday I flew AB STN-TXL. We were number 9 for push-back, and there was a line of 9 aircraft awaiting departure from 5, with aircraft at 3 different intersections. Our departure time was 0730, but we didn't roll until 0838.
I have used STN innumerable times over the years, and that was probably my worst outbound experience.
In comparison, my arrival that evening (with AB DUS-STN) was startlingly efficient and easy - and I was through security in under 30 seconds.