BD: "Simple answer is a little thing called gravity, what goes up must come down. There was a 'sampling' aircraft which flew and reported 3 distinct layers lower than had been 'forecast' plus some areas in UK are reporting ash on the ground."
Cheers
My car was dirty from early last week. I woke up to it... might have been Tuesday 13th?
p.s Listening to the R4 news before on the way home reporting there are talks about solutions to this and one of them is to fly lower.