No, incorrect.
the previous poster was correct in saying PBS does not strictly adhere to seniority. It is a function of our software. No matter how well you know the system the system can need you to do something else.
The PBS guide is a far cry from a comprehensive guide to how it acts, especially as your seniority varies.
The best pbs mitigation is to gain seniority. Bidding properties and days off is very straight forward. Ambiguous “constraints” and random coverage dates should anger anyone in a seniority based system. As someone once said, “which days don’t need to be covered”.