The rule states that he would have to be one year removed from his graduating class or, one year removed from the year his class would have graduated. Which was obviously put in for those that for some reason couldn't graduate and then dropped out.
So the loophole, if there is one, is what if he decides to forget school and just apply for the draft. Whereas he still doesn't have a diploma, and his original graduating class graduated over a year ago, is he elligible? Hell if I know, but that seems to be the point of contention.