I recently try to update my OnePlus 3T and had some trouble (boot loop and freeze) as I was using SuperSU 2.79
to root it.
Everything was fix when I used 2.82
to root.
I realize now that I met this issue several times with different OS (CyanogenMod, OmniRom, etc.)
why does SuperSu need to be updated with every new OS version?
Why do I need to