I've heard the current vacation slide mentioned several times on these boards implying that it's the reason you can get so many vacation days off in a row. The current CBA only allows you to slide into a conflict with concurrence from crew planning. The real difference between what we have now and what we would see under PBS is that you can currently bid a line that touches multiple pairings with your scheduled vacation week. This combined with the 4 days off makes it easy to stretch a week of vacation into 2 or more with minimal impact to your vacation bank. And this is without permission from crew planning, and without additional flying added to your "off" days. This translates to a lot of soft credit and days off in vacation months 2-5 months a year now that we'll be losing with PBS.