[isomorphic]

I'm speculating, but certain FCC licenses require you to transmit without significant gaps on your licensed frequencies or be fined. (The theory being that others could be making better use of your frequency since you aren't using it.) If your transmission gear goes down for whatever reason, you want to notify the FCC before others do. E.g.,

https://www.insideradio.com/free/fcc-slaps-birach-broadcasti...