I have always worn a black jacket to go cubbing. OK so its not correct, but I don't have oodles of spare cash to go off buying a hacking jacket as well. I wouldn't worry too much about it especially as the P2P lads will push the rules as far as they can go (hat silks with stars and bobbles, I'm sure that is not correct!)
Yay I was one of those P2P lads on Saturday! Ok so I'm a girly but as for stretching dress rules I was really pushing it - breeches more brown than beige, no collar on and a waterproof jacket. And didn't wear my nice boots (not riding a lunatic pointer in my showjumping boots - guaranteed to scrape them to hell), AND I had a GPA hat on. Don't worry all you purists, if I get the ride for the opening meet I'll scrub up properly, promise...