Managed to use the screenwash for the first time in weeks, due to the garage skimping on the mixture when the car was serviced in November. (We've had -18.5oC in the freaking daytime recently.) Topped it up with neat -25oC rated Halfords stuff, so here's hoping.
On the other hand, temperatures haven't gone below freezing today at all and the forecast is mild.
Rolfe.