We can bid for a different 7 & 7 every quarter, but that doesn't mean you'll get it- even if you are very senior. If your fleet is not growing it can be difficult to switch since you cannot bump anyone junior out of their slot and there are only so many slots per start day. The growing fleets will be a lot easier to transition.

If you need days off, they are pretty good about allowing a leave of absence here and there (unpaid) or you could just happen to get sick midtour (probably the most common way to get the odd days off).