I had a sililar issue with my 2014 Blue Ridge but in the front of the cap. The dealer took photos, sent it to FR and in a few weeks the approval to strip and repaint the front cap had come. Work was done and the RV never has looked better.
The dealer told me that this is not unusual for the front caps in they are the part of the RV to get the most abuse. He also told me that the manufacturers usually don't actually do the initial painting themselves... but farm it out to a vendor that gets paid "by-the-piece".
With that, the more they can get through the mill, even with a little less paint is more in their pocket, so... the result
Mine was covered under warranty so I would think they would cover yours as well. Luckily I had a dealer that specializes in RV body work and maybe that helped.
Anyway, good luck with your repair.