On the Format Clock Items Properties screen, under the Start Time tab, you’ll find settings for Nominal Start and Fixed Start Time. Nominal Start is used for Spot Breaks to correspond with the break times formatted in the station’s traffic-and-billing advert schedule. Nominal Start is also used in conjunction with Player Commands such as the end-of-hour time update syncs.
Fixed Start Time is Not Required and should not be enabled except in rare cases. (Trim Previous material is also rarely used.)
Fixed Start Time is useful, however, for its visual function in Format clocks that have only Spot Breaks on them, as it can then display the spot breaks in their timed positions on the screen. Most often, it is TrafficONED users who use the function.
