Originally Posted by
BA Loyal
The moral of the story is that there is very little logic to these decisions! You might be going from A or B or if you are really unfortunate A10 (on the bus).

There is no way of knowing until you get to LHR...
Very true, in essence asking if a flight will go from A gates or B gates is just the same as asking if a flight would go from Victor Pier in the old days as A, B and C are just different gate areas of the same terminal.
The capabilities of the gates mean that there are tendencies in where particular aircraft depart from but as mentioned above, just best to check the screens when you get to LHR.