When the courts for Scheduled Skill Level Play are not reserved or scheduled for other play options, players of that skill level are encouraged to use those courts for Open Play. The rules for the paddle rack system are here.
Open Play is available on designated courts based on skill level. It’s intended for doubles play when others are waiting. Singles may be played when no one is waiting, or players may reserve a court if they prefer. Signs near each paddle rack indicate which courts correspond to each skill level.
If no one is using a court, anyone may play there. If all Open Play courts are active, players use the Paddle Rack system to wait for the next available court. Games are played to 11, win by two, after which players vacate the court and return their paddles to the rack.