It's honestly the faster and safest route to go versus three system upgrade paths. Because not only do you have to get it on 12 (or 13) that just gets you to the 1 release. You'd have to run all the 12 system updates, then all the 13 updates and then you'd be ready for the 13 to 14 RPM, which is still BETA at this point. So that's a roll of the dice as well.
Going with a fresh install is the best bet.