How can I update OCS Ubuntu server 2.1.2 to 2.2 edition?

I setup OCS ubuntu server following some youtube tutorials, "apt-get install ocs-inventory-server ocs-ocsinventory-reports" command installed the version 2.1.2 , although my aim was to work on 2.2RC edition. How could I upgrade it to 2.2RC edition? Is there some tutorial for upgrade? or would it be easier to install the new version from scratch? Please support a newbie here :)

Best,