Depending on your system there may be issues, IMO, best to do a clean install. Depends on how comfortable you are in trouble shooting. If you want to test before installing try GeckoLinux which is a live version of 42.2
I had absolutely no problems doing that on several systems.
And upgrading 13.2 to 42.2 is even officially tested (only a standard installation though).
If you use btrfs, you should even be able to boot (and revert to) a snapshot of your 13.2 system in case of problems.