For whatever reason the union was nervous the arbitrator was going to side with the companies interpretation of the 4hr pay/credit, and opted to try this solution, which the company agreed to, in order to secure some schedule credit for the pilot group.
Bump it to 5 or 5:15 and I'm good with it. In reality, that will not happen. I don't see the company agreeing to that and we will most likely go to arbitration and just go with what he decides.
Regardless of the outcome, the company will manipulate the schedules to minimize the financial impact of the provision while maintaining schedule integrity.
I'd personally would look at it this way. "IF" you got stuck in your current position tomorrow for over a year, what would you want. The fast movement will not always last. Someone will have to be on reserve and fly crappy trips, don't think it won't or can't happen to you.