Your NAPA local league operator is allowed to set a Max Team Skill Level limit before the start of each session. If a Max Team Skill Level limit is set all teams entering the session must fall under the limit. 

Since all team skill levels will fluctuation during the session based on each team's performance, it may be possible for a team's skill level to go over the Max Team Skill Level limit during the session.  This is not illegal. As long as they entered the beginning of the session under the set limit, they are allowed to continue playing throughout the session.