Well, I know I should have gotten someone to change the information, but it's actually 5 am, it was changed a year or two back, basically so that the inbound HKG flight wouldn't leave us lounge-less. It stays open until about 30 minutes before the Abuja flight leaves.

For Terminal 5 specific info, this is the best link I know of provided by BA.

http://www.britishairways.com/en-gb/...on-heathrow-t5