Yea but its a fluid contract. He would only make max pay in 12 years if the contract didn't change for 12 years. It would be poor planning to apply today's contract to your future self. Ask the guys who had pensions. If the company hired guys who could only ride out 8 years a their ceiling they would move that money farther down not saving the company a dime.
Remember it is possible for 70% of the labor group to be at year 12 and over thus protecting it, but 10 years from now 70% could be under 12 years with some growth. The pay always moves to where the votes are.