A little history on the Clearcoat is in order.
For a long time, the Airstream plant used a really good clearcoat that was not, shall we say, ecologically friendly. They changed formulas in the 90's, and for a few years were plagued with problems.
I have a 98 Excella, and it has been to the factory twice (under warranty) to have panels recoated. By now, all of the curved end/top panels and the upper roadside panel have been re-sprayed. I've been assured that the new spray will hold up better. Right.
These days, Alcoa provides the sheets of Aluminum already coated. They are applied to the trailer and that's that. No in-house whole-trailer spraying.
When this stuff starts coming off, it looks like crap. It's going to look like crap, too, until it's re-sprayed or stripped off completely and polished. (This means, of course, that you'll be polishing for the rest of your natural life). Airstream will sell you spray cans that you can use to coat the denuded areas to protect the aluminum from oxidizing. Don't let it oxidize, it'll cost more to refinish if they have to first buff off the oxidization. The spray can will protect the alum., but it will still look like protected crap.
Don't worry too much. It's aluminum, it's not gonna rust away, just be ugly. Clean it up, save up your nickles, and have it re-coated. Take it to the factory (a fun trip anyway) or be damn careful who you let near your trailer with a spray can. Check out issues of the Blue Beret for ads.