Just let them ask their union brothers in Ops at PSL. Still haven't figure why it takes 75 percent of them to change things. That doesn't make since, but that is what they needed at PSL and it did get passed. Seems like it would be 51 percent to change things or keep them the same.
I believe this is a perfect place to have the super-majority requirement - ergo 2/3 or 3/4 must ratify the proposal. I'll put it in perspective based solely on my plant.
We're on a hybrid schedule - 6 crews working 8's normally with 12's on the weekend (days and nights cover). The vote for 12's comes up every year, with almost ever NLO/EO voting for it. The sticking point is with the NSO/RO's. Most don't want to sit in the control room for 12 hours... and who are the fatigue rules really concerned about? Bingo!
So to me, the super-majority requirement is a great thing. Unfortunately as a part of management, we don't get a choice- whatever the union wants, they get and we support (...can of worms there...), but most SRO's desire 12's as well.
I would recommend putting it up for a vote. It will likely take years to pass, however, you will see the percentages change yearly until you meet the 3/4 requirement. BTW - we DO have 2x OT during outage. Not sure how you get around that...? Creative scheduling?