1-When you say last Nov, you mean last month or last year?
2-did they take it to bare metal or just sanded and resprayed?
3-Since you didn't mention it I suppose these were not pre-existing conditions @ the time of the repaint?
My thoughts:
1- If it was just last month, then it most probably has to do with their work or material used. ( Providing no pre-exising conditions were there which you were informed of and signed off on)
Over a year ago? I don't know if that falls under " within a reasonable period of time" or not.
2-
A-if they just resprayed without going to bare metal & these are new conditions from the metal, then I doubt they could be faulted.
B-if it's due to their workanship or material used, then it's their responsibility.
C-if they took it to bare metal & the conditions were there but were not corrected properly (without you authorizing them to disregard the conditions), then they'd be responsible.
If the condition were not there and are just appearing without having anything to do with the material they used then they wouldn't be responsible for that.
Best to see where these are coming from ie base metal or the material used over it (Paint, clear coat etc.) & whether they existed at the time of repaint or not.
Get an expert's opinion in writting, and if it concerns the body shop's work take them to small claims court.
If it concerns the Manufact then contact them or take those to court.
FYI, I snatched these from a couple of sites:
Aluminum corrodes but it does not rust. Rust refers only to iron and steel corrosion.
Aluminum is actually very prone to corrosion. However, aluminum corrosion is aluminum oxide, a very hard material that actually protects the aluminum from further corrosion. Aluminum oxide corrosion also looks a lot more like aluminum (dull gray to powdery white in color), so it isn't as easy to notice as rusted iron.
When iron corrodes the color changes and it actually expands. This expanding and color change can produce large red flakes that we all know as rust. Unlike aluminum oxide, the expanding and flaking off of rust exposes new metal to further rusting. This is why it is so important to provide a barrier so rust doesn't start.
&
Scientific discovery: Why aluminum doesn't rust: 5/00