Ubuntu 16.04 was just released, but, if you want a newer 16.10 release, you are able to upgrade from 16.04 to the upcoming bleeding edge 16.10.
It is quite easy to upgrade from a next development release, in fact. I just upgraded from a 16.04 to 16.10 running on a POWER8 in less than 20 minutes.
In order to do so, run the following steps:
At first,changes the Prompt line at /etc/update-manager/release-upgrades. It should point to lts, meaning that this distro will only be upgraded when a new LTS is released.
Change it to normal, so, you can get the 16.10 release. That said, the line should be:
Now run the following command:
$ sudo do-release-upgrade -d
Answer the expected questions, usually with a Y and your system will be rebooted with the 16.10 release.