Upgrade suggestion

Hi all, I have an ubuntu 15.04 and owncloud 9.0.9.
This ubuntu version it's not supported anymore, so I can't upgrade owncloud from the repositories.
I'm valuating 2 options:

  1. Upgrade owncloud without upgrading ubuntu
  2. Update ubuntu and owncloud

Considering I don't have physical access to the server, I'm a bit scared about upgrading ubuntu from 15.04 to 15.10 and then 16.04.

Ubuntu 15.04 has apache 2.4 and php 5.6 so it has the requirements for owncloud 9.1.
My idea is to uninstall owncloud (apt-get remove) and upgrade owncloud from the tar.gz.
Shall it work?
I wonder if

  • will /var/ww/owncloud be removed?
  • will mysql-server be removed?
  • will I have to reinstall php dependencies?

Any other suggestion?

Have you considered backing up and importing your data in the updated ownCloud? As described here

Regarding your questions: I don't know and can't reproduce this. But I suppose - yes.