Love it - I remember Twycross Zoo. When I was at school we used to go to discos held in Twycross village (it was the place to be...) Wasn't it the zoo that had the chimps that did the tea ads???
Well, I can't see what else it could be if it's not a male orange tip, but it has lost so much of its colour and underwing markings, that it is a pale shadow of what it should be. You've done a great job of recording it, though, Phil.