I have had some play partners who still had their foreskin. I have never gotten in an ongoing relationship with them so I haven't taken the time to ask this. When you are getting oral sex is it better if your foreskin is pushed back or to just have nature take it's course with it coming back on it's own?
I can only speak for my uncut self, but the skin usually goes back when I'm hard anyway. You're really best off asking what your play partner likes even if you're not in a relationship. Come to think of it, that sounds like good advice for a lot of other things.
The best option with your case is to do an "at home" "correction". All you have to do is get make sure your partner is horny, throw some rubbing alchohol on it, and then while pushing the head back, cut really fast with a sharp knife and throw some more alchohol on it. As soon as you do it he'll be in great pain and also pleasure at the same time so the best method is to suck him off for about an hour. You'll have a mouth full of cockblood but it'll be cool. Afterwards put some ice on it and it will eventually scab over, and be healed in about 2 weeks. He'll love you for it.