Originally Posted by
Big E 757
At Delta if pbs gets to the bottom of your bid and hasnt put enough flying on your line to satisfy the line construction window, it works backwards back up your preferences and drops the last one and sees if that allows a trip onto your line that satisfies the LCW, then drops the next higher preference, etc. etc.
That’s Denial Mode. As was previously mentioned, Unstacking puts stuff on your schedule prior to looking at your preferences. There’s a Delta PBS gouge pdf out there that explains it all.