Now creeping up on 600 miles
..aiming for 622miles before refilling. If I run her dry, that'd be 622/12.1 imp gal= 51.41 imp mpg (622/14.53 US gal= 42.81 US mpg)
I reckon it'll not be as low as that- Aiming to fill her with 1/8th of a tank still showing.
then she'll get 5 or 10L veg oil, and a diesel top up