Reply to everyone.
It's obviously true that these birds are spreading. Thanks for all the comments. I'm still left wondering what the birds in the Isle of Wight were doing bashing themselves on the glass. Perhaps ornithologists don't read the GW blog. I'm just back from the IoW and although we stayed in a different holiday cottage, there were more birds banging on the windows — a chaffinch this time.
Reply to Callum.
It certainly looks like a green finch to me.