The United assignor has many factors to consider when assigning games and is responsible for putting the best-qualified referee teams on the field while supporting new referee advancement.
Each season, a group of referees from previous seasons who have expressed interest and ability to become more advanced referees will have priority access to games through the Promotion Program. Each new referee will be mentored in one game. Around 80% of referee slots are delegated to Preferred Referees.
Going into each season referees are informed what segment they fall into.