I have now put 3,300 miles of wear on these tyres, and the mpg is on its way back up. On Saturday, it was mild and dry and on my trip over to the south of Edinburgh, and back my ScanGauge showed an mpg figure back nearer what I was experiencing with summer tyres in summer weather.
Today I filled up the tank, and the calculated figure was 49.7 mpg. Now, considering the snow, ice and poor conditions I have experienced during this tankful, I am really quite pleased with this figure. My first top-up after 2018's Beast from the East was 50.0 mpg, so this is comparable. I am interested to see what the All-Season tyres, now they are worn in, return in the spring and summer.