you know jughead, I didn't think of it quite in that matter...
so, to keep it simple: during the "current" contract period, there are things that the company wants to adjust in their favor. depending on the level that these items rise to, then labor can reply with an increased bar of their own. each group does its own "cost-benefit analysis" and if the two lines meet, then they will each approve the new contract.

I was admittedly looking at it from a narrow lens (based on things that I read here and hear in the ready room)... one that is naturally biased. I hadn't considered that the new contract would have changes that were favorable to the company. In hindsight, that was pretty naive.