Yes it is LTS until 2021. Check out Wolfman covered how to do an upgrade in his post install guide. However my advice to you would be to download redobackup:
http://redobackup.org/and for good measure open your '/home' folder and press 'Ctrl+ H' to show all hidden folders then copy and paste everything into a new folder on an external drive.
You will find that it is not as customisable as earlier versions of Zorin.
Whilst it has reached end-of-life I am going back to Zorin 11, deleting Windows 10 as Internet connection is poor so net based games don't always launch and will see if I prefer SolydX or Debian which is more customisable by all accounts having taken a quick look at xfce on Debian instructions.