The current modus operandi of most pirate radio operators is to run as a legitimate internet radio station - remove all reference to the FM broadcast frequency

The current modus operandi of most pirate radio operators is to run as a legitimate internet radio station - remove all reference to the FM broadcast frequency from the website and promotional materials, promote yourself as "the internet's no.1 grime station" or whatever. Then, when Ofcom come calling, the FM transmission is "someone relaying our internet broadcast, we don't know who it is."