Most commercial broadcast stations over-schedule each hour by a song or two because the music director doesn’t know in advance what the commercial content for the future days will be. The extra content is there to ensure the hours will not come up short, less than 60 minutes. Even when commercial content is not a factor, there is the possibility that some hours may occasionally get several longer songs scheduled which then result in the hour being over-scheduled by several minutes. If numerous hours are over-scheduled and Time Updates are not used, as the day progresses the start-times of the songs-and-hours may be shifted to much later than they appear on the M1 schedule. To avoid this, Time Updates are used. These are often called “hard sync” and “soft sync” commands. Here’s a video showing how these commands.
