Hi,
In reply to the holding question most aircraft entering the hold from the east will decend from there previous altitude to FL150. The controller normally asks them to decend further as they get closer to their previously cleared altitude. Normally they ask aircraft to be level (between FL 90 -110) 5 miles before Lambourne. They then transfer to the director which controls the traffic from the north and the south side of the thames. Which ever has heavier traffic normally gets prioty but this varies tremendously! If I am a wrong please don't shout at me because all this info I get Is from spending an hour listening to my Airband radio and trying to make sense of it all! Please correct me if am wrong as i personally would like to learn more about the holding patterns for LHR.
Many Thanks
Dave