For a format like TrackSprint, it means you get another run, or they get another run. In a format like Time Attack, if there is passing allowed it will depend on your level of experience. Typically, if you’re new it means all passing will be by “point-by” and those with the most experience may be allowed to pass without point-bys – which is known as “open passing.” It’s best to check with the organizers or “Supplementary regulations” of the event you’re planning on going to.