Thats the plan bud, Clive has just called and he will confirm 12th or 27th August by the end of the day, he is in the racing season so is pretty busy.
You book the track time with Silverstone and pay for the tuition on the evening.
Open pit means no time limits on the track, the only change to this would be if it got very busy so they may have to limit it, cant see that happening though.