Stuff I've seen says minimum 6 months, more likely 12 to return to action. Sorry to say, but I think that's it for JJB. With him likely to be back only in time for the very back end of next season, the question needs to be asked whether he'll be worth a deal for 2017, and given fitness concerns stretching back to 2012 I'm sorry but the answer is probably no.
Real shame for him to go out this way, but no doubt he'll be staying around the club in some capacity, a true Leeds Legend.