I agree with the last post.
Think ahead & avoid full tanks of WVO / biodiesel going into cold weather. If you want to wake up a attentive service station (do these exist anymore) attendant, start filling by putting 2 gallons of RUG in the tank & toping off with diesel!
One solution is the diesel heaters. Do a search on this site. Greasy_Beast drove from the E. coast to Montana using 2 gallons diesel in such a heater, heating his WVO system. Added benefit is warm startups with warm cab. Pricey, but these units are built for semi trucks & with proper care, should out live you.