If the tours are not fully booked, you may be able to get onto a tour on the day.
I visited 'AC for the first time last October. Great setup and nice to see her undercover and out of the elements (I wish G-BOAF could have something similar in Filton)!
Not too fussed about the tour as I've been onboard at Filton, Brooklands, E.Fortune, Duxford and Sinsheim in recent years and will probably only have time for a brief walk around anyway, but it will be good to see her.