If you're referring to scheduling alert 20-25, then I would just try it. The resulting knowledge would be worth a lot. The computer doesn't care as long as the keys fit the locks. Let us know. I don' t have any PB days but if I did, I'd try it just to see. It automatically uses as many PB days as the trip or all PB days if not enough are available. The request is to limit the number starting with day 1. The request form just prevents a phone call to scheduling. The intervention to limit PB days is still manually done by a scheduler. My take away was to use PB days and then limit them to 1 when the day 1 credit was high.