What does this mean" Park no earlier than four hours before the scheduled trip start

The phrase "Park no earlier than four hours before the scheduled trip start" means that you are allowed to park your vehicle at a location only if it is within four hours of the time when your trip is set to begin. In other words, you should not arrive and park your vehicle sooner than four hours before the designated starting time of your trip. This guideline helps ensure that parking spaces are optimally used and that vehicles do not occupy the area for longer than necessary before the trip.