Here's the proof, not the most wonderful pic though...
The redpoll was joined by two more, slightly better photos of them. The rump and back certainly have a white ground colour even if they are heavily streaked, islandica I reckon.
Siskin and Common Redpoll
Various pictures of the three
Also yesterday an Arctic tern on The Shunan, a House Martin through the garden. The seawatch at Yesnaby produced about 40 Bonxies going south, uncountable as most were above my head and I was staring out looking for distant Poms.