O-2D7 gives us a few tidbits from the reshoots done a few months back in England. This has to do with a change from the original script for a small detail:

Originally it was said that Count Dooku was going to control his ship with his mind. There would be no need for controls because he could control it himself. In the latest making of video, Obi-Wan is wearing a headpiece like that when he gets inside the new Starfighter. Perhaps that is just a set piece or it could be that perhaps they transferred the idea to him instead of the Dooku character as originally planned.

This is why I'm writing, since at the Ealing reshoots they filmed on that Friday in April they did something different for the Count. They filmed him at the controls of the Solar Sailor leaving Geonosis. A second later they also filmed Christopher Lee in the same vehicle, this time arriving on Corusant. An interesting but small change to an idea they had when they first shot the film.

Incidentally, Friday was supposed to be the last day originally but they added Saturday for the wedding scenes and to add Sio Bibble (played again by Oliver Davies) into the film.