At this point, you think there's still high risk?
I saw the command to perform the update for Ubuntu proper. Just wasn't sure if the same should be used on an ubuntu variant.
There is no risk when you back up your shit.
The clean install is indeed a clean install. You will thank yourself later.
Or.. you can switch to a rolling release model distro such as Solus or Manjaro.
But getting back to your current situation: as you're not on to a rolling release... It is very wise to do a clean install.
Linux geeks doing what Linux geeks do...