There are under 200 tankers used by the MILITARY at the last count that hold 20,000 Lars of fuel each mostly diesel and aviation fuel, they will all need flushing if they are to be used for petrol. Most fuel carriers in the military are small bowsers that also will need flushing. Many of the tankers are used by the RAF and remember, they only work Mon-Fri 0900-1600 hrs
Will you see some on the road, possibly, will they have much effect. I’ll let you do the numbers.