That would be true. It used to be you could bid a schedule putting all your training, vacation, etc. over scheduled trips giving yourself lots of days off. With PBS, everything is pro-rated and you will always feel like you are getting shafted. If you work for a dishonest company, they will manipulate it forcing everyone to work how they see fit. They can force almost the entire company to work 18 days/month for the guarantee if your company does not have decent rigs. PBS is not a good thing. It's sad that some unions actually give up concessions to get PBS and view it as a win. PBS sucks.