They definitely got a lot out of the Standing Vacancy LOA. Not having to train DECs as FOs then wait until a vacancy to displace them into a CA seat probably outweighed the immediate CA pay at vacancy award. A full additional training cycle with hotel, sim and instructor costs had to be a far greater expense plus whatever other pay withholding expenses if they tried to fast track them out of training seniority order.

I don't think the company would have played ball to settle the flow though grievance without it but I also don't think they wanted that training headache indefinitely. I don't know how much more they could have extracted before the company walked to arbitration and adapted to the training headache but that's always the second guessing that comes with reaching a settlement instead.