This is a false statement:

"our final longevity for pay is related to where we fall on the final merged list."

Pay is based on longevity and position held (airplane and seat). The only thing your relative position on the ISL has to do with pay is the pilot's ability to bid for equipment, seat and schedule, these thing are ISL related. Longevity determines what year pay scale you will receive for the airplane and seat your seniority can bid.

Please compare apples to apples.