I'm not sure (though I heard so) it's the case for RY pilots, but there are other means of obtaining submission.
Typically the agreed worked conditions are substantially better than those in contract. And should you apply work-to-rule, the company plays the same card. Thus 5 on 4 off turns into 6 on 2 off; 9 days off/month turn to 7, Yearly HOL award changes from 35 to 20, "available days" change to STBY and similar.