Smcp feature generation, name with caps or lowercase

I’m building a font with small caps. It is documented that glyphs expects lowercase names for the SMCP feature and uppercase for C2SC. So should I go with lowercase and SMCP? Or is there a reason to do uppercase and C2SC?

There is better copy-paste character preservation from PDFs in some versions of if you have separate UC and LC smallcaps. But frankly, I don’t think it’s with it. I don’t do it.