New Illustrator converting colorspace of named spot from CMYK to RGB

[defaultw1ercj4wqoog]

Has anyone else seen this happen to an existing file when opened in the updated Illustrator? 

Is there a way to STOP it? We have hundreds of files with defined CMYK spot colors. Having to check every file/color is going to be a real productivity killer.

[Ton Frederiks]

Have not seen that. I have seen problems with spots and CC libraries, but not what you describe.

Can you explain a little more what happens?

Are these Pantone colors, and if so, why use CMYK values?

Are these your own created custom spot colors?