Just for giggles I re-found this web app for plotting the lay of the land between two points.

I wasnt sure of the height of the antennas at Sunderland but set it to 100 mtrs(300 foot aprox)

https://www.scadacore.com/tools/rf-path/rf-line-of-sight/  the web address.

Regards Nigel - G0JKN