On the face of it, burning a little oil to go somewhere warmer when the UK is cold in winter is no less logical than staying put and burning oil to keep warm there. If it is cheaper then it is more efficient, but it may not be cheaper. Sepearte from efficiency, it is probably more effective. SO if one looks for a justification for removing the cold weather benefit from people who use it that way, it doesn’t seem to be the one presented at present – that some people have gone where it is warmer.