I think there is another reason besides the CBA.

I think the company has the ability to "massage" the results if they run into problems. I recall serious problems in the past whereby entire BES's (Base Equip Status) bids were flawed. I recall the EWR 737, EWR 756, IAH 756 (twice) and IAH 737 being so screwed up they had to re-run them. The runs and the re-runs affected thousands of pilots in cascading fashion. These issues took place in both November and December, two very important holiday months for pilots.

The company probably learned some lessons in those instances and wants to view and review the results and massage them if needed. I take exception to terms like "seniority within feasibility", "seniority homogenization", "overall solution constraints", etc. If we had something like seniority locking the schedules would be more in line with holding what your true seniority would allow and take away the company's ability to manipulate the award.

I have seen junior pilots to me get what I requested and I get something 180 out. No training conflicts, no vacation conflicts, no military leave conflicts, nada. You file a discrepancy and get shatt upon. you file a grievance and the union does nothing about it.

ALPA pushed for PBS but the company truly controls it. It is just not transparent enough for me.