Attrition is not happening at a rate that will cause management to get CBA hammered out quick. Bozo says he's leaving but he has to get a call, interview, class date and ultimately resign. That's probably a 6 month process on its own. So, I don't think you're going to see the floodgates of attrition ever open. If we don't have a CBA in July, 2018, well now its probably a different perspective for guys leaving. Back up 6 months from July and you've got January, 2018, and when those "nay-sayers" will say its time to put in apps and call-in favors.
Most are sticking around right now because they've got a major stake in B6 being a career airline. Like Bozo said, everyday that goes bye is another day towards 65 and what "you've got left for a career". A decent CBA (IE The Hawaiian examples of successful negotiation and mediation) makes starting over somewhere else worth buckling in for the ride.
-Bubs