Since the London tube strike was due to start at 1830 people were anxious to get away immediately prize-giving finished. I left at 1615 and drove back via the M25. There was a long slow drive at about 5 mph for the whole length of the Dartford bridge due to the restriction of the toll booths. I paid my £1 toll fee, continued my journey but unfortunately I found that the slip road onto the A2 had about a half mile tailback that was likely to hold me up for at least 30 minutes. I came out of that queue and continued on the M25, car windows open to allow the cool breeze to refresh me as the late afternoon sun was still beating down on the earth. That turned out to be an excellent decision and I arrived home at 1810 without further hold up.