Was just in BA two weeks ago. No e-gates on arrival. On departure, I could choose to go e-gates or regular. The regular line had a significant wait of maybe 20-30 mins. The e-gates were not very clear on who was eligible, but I tried it anyway. The computer could not read my (brand new...) US passport and I was diverted to a manned "red lane" counter that had zero wait. Even with the screwy computer and manual review, I was done in less than 5 mins.