Can you be more explicit please.
I assume you did nothing else but reboot?
Or did the flickering occur after the update but while still running the older module before rebooting?
Narrowing this down is important to know the cause. The driver modules are loaded at boot, but other packages may have been updated and caused issues.
In fact, my system had updated the driver but I had not rebooted. I tried running nvidia-smi but it failed due to a version mismatch between the driver loaded and running and the other nvidia software (specifically NV??) that had been updated so it no longer matched the loaded drivers. Sorry I did not write down the message, I just rebooted and the issue went away.
This is just to say that the flickering may have been related to mismatch between the kernel module in use and the other supporting software. Even the DE packages related to the nvidia drivers may have been part of the issue.
A reboot reloads everything so timing of when the flickering occurred may be important to determine the cause.