You sure about that? I've always thought it was two years, and everything I'm finding says that 2016 draftees have to sign before the 2018 draft. We drafted Giorgio Estephan in the 2015 draft and because we didn't sign him he went back into the 2017 draft. He was then undrafted, and now is an invite to Wild rookie camp.
Hmm...good point. I always thought it was three years but maybe that changed with the latest CBA. Your Estephan evidence seems to indicate it's two years, sorry about that.