Man you got lucky. That bulletin Michelin put out about the brown letters said it was not a warranty-able issue. Then they do this? Good for you man. Mine are over a year old so they won't do the same for me. You know, my new tires they couldn't even get the blue dye off the letters when I first bought them. Never seen anything like it. You should be able to wash that stuff off with kitchen oap and a sponge. But this stuff wouldn't come off with hot soapy water and the stiffest bristle brush you've ever seen, or, denatured alcohol. It even fought lacquer thinner. I am starting to wonder if something in that blue dye is the actual culprit.