It depends on how big of a jump from one version to the next.
Edit: TL/DR shader folders are based on the Star Citizen game version, not the Nvidia driver versions as far as I've seen.
You can find the shader folders under "%localappdata%\Star Citizen"
Alternatively the full path:
"C:\Users<username>\AppData\Local\Star Citizen"
On any major version changes, there is a completely different folder for shaders (ex: 4.3.2 -> 4.4.0)
On minor version changes/updates the shaders folder is rarely shared with the previous version (ex: 4.3.1 -> 4.3.2). Although I haven't noticed this happen in a long time.
I've noticed that usually very minor version changes/hotfixes that come out within a few days of a previous update will share the same shader folder with a previous version (ex: 4.3.2-live.10452200 -> 4.3.2-live.10591185).
The worst issue I've seen happen because of this was when they first introduced caves. I was standing inside of a cave, and a friend could not see the cave even when he tripped and fell right inside of it. He needed to exit and clear his shader folder before he was able to see the caves.