The plot changed! They did this morning's bit yesterday and night stopped at North Weald. They overflew Duxford 30 mins ago and departed - they didn't land as scheduled. I presume they are flying the rest of the morning schedule up to the Biggin Hill stop a bit early. No doubt they will stick to the planned times for the London overflight.
Things at Duxford seemed a bit exciting judging by the radio traffic - they were formating on an Aztec of all things, with another Aztec standing off, presumably with press and TV cameras. Pity about the Aztec - spoiled the picture for me.