TIA doesn't have a clue. I don't even know where you came up with that stuff your spouting, but it's absolutely wrong. I know it and I'm not even in the industry any longer. Eveything, including he definition of seniority, is agreed to in labor contracts. It even varies from labor group to labor group. In essence, it is between the company and the union, since it is agreed to by the company, but in the interest of harmony they never get involved in it, at least never that I've seen. The company can limit the benefits associated with seniority (unless it's specifically dictated in the contract) like what LCC did when they revised the boarding status of certain employees and retirees, but even that wasn't absolute since it was dictated that certain employees were to be given different priority in their contract. Just one of the many jillions of reasons the unions try to cover all bases and possibilities in their contracts. All the contracts that I've looked at have entire sections covering any sort of "change of control" of the company, not just merger, and it is these sections which are resulting in entirely new contracts being negotiated even as we speak. Most, I would think, will end up before an arbitrator, but this too is agreed to in the contracts. Only one thing I am sure of, TIA ain't got a clue!