Sounds like a perfectly normal display by an experienced display pilot in a real Spitfire and not one of those silly wannabee replicas. The original post strikes me as something the Daily Mail would publish looking for some 'shock horror' attention. It wouldn't be NOTAMd if it was an illegal flight now would it?
Maybe this is part of a planned event. If it isn't, he or she may be about to enter the mother of all piles of do-dos.
And your display flying experience on type (Microsoft Flight Sim hours not included) would be??
Move along please, nothing to see here.