My guess is that if we are going to use flying from a different month than we have already then they have to create all new pairings for that month. The pairings in NavBlue are not simply our current pairings with pbs rigs laid on them. They are entirely new pairings optimized to the new rigs. My guess is that takes time and resources from crew planning.
The other question is for what purpose? If everyone is messing with their bid on the mock bids you don’t really know if you’re getting accurate results. The only way for you to know if the changes you’re making are working is if only you change your bid and every other pilot senior to you stays static.