Was there...
I was there watching from the ground - to me looked like another high speed pass - I watched the pass with the 2 aircraft opposing then turned to say something to my kids and saw the fireball, so didn't see the final part of the run. What to me was notable was there was no smoke from him (they'd been running smoke on each of the passes before and his partner had smoke on).
The angles/trees at Oulton Park make it very difficult to judge AGL for someone in the crowd. I know in previous years I've watched other displays from different vantage points on different days and seen very different apparent heights for the same routine.
What will live with me was watching the other aircraft circling knowing what had happened until the first responders got there. (There was Cheshire Police on the ground doing displays at carfest who left within seconds so not long at all).
Organisers did a great job of ensuring the show went on - but also held a minutes silence and a number of other speeches remembering him.
RIP.