Pretty happy if this is true, although the article is about the M4, I am hoping the same would apply to the M3. I know this is just a rumor, but that would be epic if a lighter CS was available with 6MT/RWD.
https://www.motor1.com/news/511541/bmw-m4-cs-csl-spied/
"Rumors suggest BMW will pair the potent mill with a six-speed manual gearbox and rear-wheel drive."