I have version 4.2.8.2. My Ubuntu seem not to upgrade it authomatically to 4.4 or 5.0. How to do it?

I have a few changes done grammar installed, epub plugin etc. But I would like to pass to the 5.0 version. Why Ubuntu doesnor do it authomatically when it updates all the software?
How to make it do it without having to install the new version from 0 and then having to redo all the settings and extras?

You will need to complain to ubuntu if you have used an Ubuntu PPA. If NOT from an Ubuntu PPA, then ubuntu will never update it anyway.