If you are at the bottom of the UAL seniority list, how is it that you expect to not be at a similar relative position, ie towards the bottom, of the new isl.

If the merger would not have happened, once recalled to UAL, you would have assumed your position at the bottom of the list. So you would most likely be an A320 F/O.

After the isl is put together, I don't see how you would expect to be too much better off than a junior A320 F/O.

The arbitrator will have to work this all out. I am trying to understand your thinking in trying to justify something better than where you would have been had the merger not happened.
Assuming that you had an airline to come back to and that UAL wasn't pieced out in an auction like Pan Am was.