There isn't a way to upgrade between OS releases

danrabbit from IRC offered the information below:

As far as I know there are a few issues.

Update manager disables ppas during upgrades. So since we're using ppas it wouldn't work.

It would need to be patched to used lsb_release -u so that it sets the repos to "trusty" and not "freya" (which doesn't exist)

Lewis Goddard: If we were to patch the update manager in Luna, it would be do-able, but there could be a lot of other issues we haven't even seen because it hasn't been done yet.

Launchpad Details: [#LP1486694](https://bugs.launchpad.net/bugs/1486694) Amelia Rose Khan - 2015-08-19 18:11:28 +0000

Beginne damit, den Upgrade-Pfad des Update-Managers nachzuverfolgen und zu untersuchen, wie er PPAs deaktiviert. Untersuche anschließend das vorgeschlagene Verhalten von lsb_release -u und wie Repositories von "freya" auf "trusty" abgebildet werden. Die Aufgabe ist abgeschlossen, wenn ein OS-release-Upgrade-Pfad definiert und seine Auswirkungen auf PPAs und Repository-Namen überprüft sind.

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