Not to be funny bud, but I don't really agree with what you're asking for. If the GB sold out quickly and your spot could be offered to someone else searching for it, I'd totally understand and commend you for doing so. But even a couple hours later from live time, the GB is still open with copies left so the demand simply isn't there for your cancelled copy right now.
I myself joined the GB first at HDN as frankly I can't be arsed with HDZ's pathetic website antics anymore, I decided to take the easy ride then shortly afterwards found out I could have actually ordered direct afterall and saved $20+. But I wouldn't then feel it's right to do that then ask for my HDN order to be cancelled. Too messy for my liking.
Anyway, just my honest 0.2 cents and no offense intended. If you got what you asked for, good for you and your wallet