It's actually graduating class. So if the kid is already in college then 3 years, but typically they haven't started college yet before the draft, so in the vast majority of cases it's 4 years. CBA text:
(c) College Players.
(i) If a Player drafted at age 18 or 19 is a bona fide college student at the time of his selection in the Entry Draft, or becomes a bona fide college student prior to the first June 1 following his selection in the Entry Draft, and remains a bona fide college student through the graduation of his college class, his drafting Club shall retain the exclusive right of negotiation for his services through and including the August 15 following the graduation of his college class. The Club need not make a Bona Fide Offer to such Player to retain such rights.
With name changes you can only bet with one person at a time, if newfy doesn't pony up (which I totally expect him not to) then you're on. Let's give him a week.
Loser changes his user name to "Kienan Draper's #1 fan".
FYI, by the time Buium and James graduate, the Wings will have plenty of bottom pair D and bottom 6 wingers, I see them signing elsewhere even if they become pro.