https://www.ofcom.org.uk/spectrum/interference-enforcement/spectrum-offences/illegalbroadcastCopied and pasted from the ofcoM
link above is the following:.
Summary of offences
Anyone involved in illegal broadcasting is committing a criminal offence and could face up to two years imprisonment, an unlimited fine or both. See sections 36 to 38 of the Wireless Telegraphy Act 2006.
You may be committing an offence if you know, or have reasonable cause to believe, that unauthorised broadcasts are being made, and you:
keep
a station/apparatus available for its use;
allowing your premises to be used;
advertise;
promote;
provide content;
or otherwise enable
the broadcasting, including managing or rendering any service that will facilitate the operation.
'Think' may not turn out to be exact! Unlike my grammatical assessment of ofcoM's 'Summary of offences'!
Let's hope they are equally sloppy when it comes to catching 'UNLICENSED AM MODE OPERATORS' and their supporters