For whatever it’s worth I highly recommend a fresh install if you can swing that.
Yeah, I thought so. It's just loosing everything perfectly tuned and doing it again a bit pain in the neck.
But in the other hand, I don't do this too often, once per year is bearable.
By the way, I'm living in China and SSDs here are dirt cheap, so I thought maybe to get one external 256gb and Install Catalina on it.To see how it works, while I can switch back and forth if needed to. When I'm sure that it's completely working use CCC to clone it into internal NVME ssd.
Did some research yesterday I have to move kexts from "Other" to the folder with version of OS so in my case it would be "10.14.2"(move my currently using kexts there) and "10.15.2"(copy all the newest updated kexts), have you ever done this?
Other than HEVC not seemingly working with my 570, everything else has been completely flawless on Catalina for me - surprisingly to be honest.
"Sidecar requires hardware support for HEVC/H. 265 video encoding, since Sidecar operates not by sending a typical display signal to your iPad, but by sending a video stream over either Wi-Fi or a connected Lightning or USB-C cable"
One of the main reasons I want Catalina is being able to retouch photos with apple pencil, and Sidecar needs HEVC support, but as I understand CPU deals with it first. Wonder whether this going to be an issue.