I found a video tutorial on this on YouTube.
Unless I missed something, it appears SWA uses pre-published line of time bidding.
I think a lot of Delta pilots like the level of control PBS bidding has given them.
I don't think there's a way to bid your schedule with PBS and not have your vacation also in the PBS system.
So I don't understand what you mean when you say "non-PBS vacation". How would that work?
For me personally, I'm a simple guy. I'd like to get more hours per day on my vacation and I'd like to have more days of vaction per year. But if you have some other idea, I'm always ready to hear how I can get more time off and more money!