You sirry Iriot! ©

I hadn't forgotten I had them, just where I'd put them, so they spent the winter in "The Computer Shack", twixt 14˚C over night and 20-21˚C during day instead of the much cooler Kitchen.  
As a direct consequence they've chitted way too early - BUT - to quote Baldrick:-
"I have a cunning plan."©  
I've said, for years now, that volunteer spuds only come up when they're good and ready and the Soil temperature suits them. ergo the blue ones will go out, deep enough to avoid frost, what little we're likely to get and, hopefully they will do exactly that.  Only time will tell.
The reds and the suspected Pink Fur Apples behaved much better.  Must try and remember - maybe blues are "1st early"?