Let me clarify to all.
Yes, Cibachrome was coated on RC support. IDK the sheet sizes available, but it was out there in cut sheet. At that time, we were informed that it was discontinued due to problems with separation of the RC at the edges due to destruction of the fiber paper in the sandwich structure of the RC. This seemed reasonable as our experience showed that coating DB materials on FB paper itself caused severe deterioration of the FB. Our own DB material was coated on a similar support to the "plastic" based Cibacrhome of that time. I have a small roll of it here in my lab. Just the support and not coated. Grant Haist found it in his darkroom and gave them to me not long ago.
As for fading.... The only thing I see with Cibachrome is not fading. It is the formation of brownish spots at random on the prints. And the only place it occurs is in the folder with Cibachrome, Type C and Type R prints. The C and R prints are getting red spots on them, and when you open the folder there is a faint odor that can be noticed. IDK the reason, but these were all properly processed.