Official road closures and parking restrictions have been revealed https://www.rushmoor.gov.uk/airshowtraffic
Main issue is that the Fleet-Aldershot road along the west side is closed to vehicles, and pedestrians for the week before, week of the show, and departures 12:00-17:00 every day. I believe that the canal tow path will also be closed to pedestrians as in was in 2016? Basically there is no naughty field at the western end of the airport.