Originally Posted by Quint

Unstacking is a sorta-downside of PBS. I'll try, in a nutshell:

Since you are building your own lines out of the trips in the pot, everyone is going to request Christmas (or any big holiday/event off). PBS will comply. Problem is you're going to end up with a ton of open trips over said holiday. More than the reserves can cover. So PBS will, in reverse seniority order, "unstack" enough of those open trips and rework the junior lineholders schedules until the open time over those holidays are manageable. Thereby having those guys work over the holiday when they otherwise could have held it off.

Sounds really bad, but if you think about it, under line bidding, the company would've built the lines to not have that many open trips over said holiday to begin with, so it's really a wash.