In the UK only "central" England and south transmits data over the mobile network. In northern England and Scotland, the data is transmitted over UHF radio.
Sorry yes, I should have been more specific. The important thing is that it is reasonably well encrypted. Its not like the USA where they just yeet it in the clear for all to see.
The downside is that the non cellular backhaul is provided by arquiva, who are shits.
In the UK only "central" England and south transmits data over the mobile network. In northern England and Scotland, the data is transmitted over UHF radio.