Hi, yes that happened to mine as well, in my case the dregs that were left in the nozzle from prev user ran over the tank as i lowered it into the filler, i immediately grabbed some paper towels and wiped away the fuel. Too late! By the time id paid at the kiosk and got back to the bike the blistering was already starting, came off in a large strip. Apparently the new E5 and E10 is very corrosive especially on new paint ( who knew?) Anyway im guessing you originally used same painter as me in Leicester area, i contacted him and he managed to blend the area back to as new condition, you now def cannot tell, yet didnt distirb any of the striping that was already on ( which is expensive to replace). Yes it is a fair trek but he did a fantastic job. Another option could be to courier it both ways save the drive.
Hopefully youll get it sorted and new painter will do a good job. There are local painters i could have used but didnt want to take the risk