I am having another go with the 15m earth-electrode antenna and 5mW ERP on 474.2kHz WSPR this evening. Unless UK and near continent activity picks up, it could be another fairly fruitless evening.
Certainly it is a lot easier getting DX spots on 10m.
UPDATE 1810z: Not long ago M0PPP was a reasonable signal at -23dB S/N on 474.2kHz WSPR. He is in the Barnsley, Yorks area (IO93gm) and should be "off the side" of my earth-loop. Midway through his TX burst there was a slight break and frequency shift too.
UPDATE 1940z: My only reports so far are from G6AVK (78km) again. I am copying F5WK (364km).