The orange peel happened in more than one year, so I don't know if I would call it a defect per se.
I have a "B" code black with orange peel, pretty sure one of my old WSMs has it, I think I have a patented 18.5" with it, and I think an "A" Smokey Joe too.
Is it the porcelain they used? The steel? The temp they were baked it at? Humidity or other environmental factors? Don't know.
Don't care either. I love the way it looks.