How early should I arrive at Waddington?

Never been to Waddington before but fancy a trip as something different.
I normally try to arrive at a display, be parked up engine off by 10-10:30 at the latest.
What time should I expect to arrive at Waddington to avoid the crush?
BTW what’s Waddington like as a mixed, air, ground, stalls type venue?
ATB.