Will Phoenix canariensis survive in winter?

Canary date is marginal Louvane. Where in the UK are you?

Boy I had to look to find this after your PM Louvane. You are a little bit warmer than I am on the Yorkshire coast but believe it or not, not a lot. I have 4 P. canariensis out in my south facing garden up here. For the first couple of years I just threw some straw over them then a piece of hessian (sacking) before first frost. They are now 5 or 6 years old and no problems. I still watch the weather forecast and keep some hessian handy in case they say very low temperatures. If you just bought it I wouldn't plant it out now, it needs to harden off and although the soil will be warm at this time of year it could still shock. I think your precautions are very sensible and I would just fleece (or hessian) it and leave it out. If it is very small then bring it in. I would plant it out next late May or early June and then just watch the forecasts next winter.