See the RED warning on Tweakers Page.
BTW, waiting for 18 months before trying out CC and continuing to use CS6 saved you a lot of money. Around $ 900 in the US, but a whopping $ 1500 in Europe. Congrats on a wise decision.
Not that I have any intention of doing it, but does that also apply to earlier versions of perpetual license?
Wild guess is that it only applies to CS6, not to previous versions. CS6 can be installed from the CC subscription, previous versions not so.
The caveat is that CS6 users better deactivate CS6 before installing CC, to avoid problems with the activation limit.
I have a dedicated CS machine and laptop (win7 sp1), both old school with legacy hardware for legacy work and folks whom still want a DVD, etc. I have newer machines strictly used for CC (also win 7 sp1). Both platforms have their pros and cons, and I don't have to mix it up.
If you have outstanding work/clients and depend on that one machine, then I would not install the trial unless you're committed and fully understand the RED warning in the tweaker's page as cc_merchant pointed out.
That said, I have CC 2014.2 working wonderfully.
Many thanks for all your help. Really useful answers.