upgrade from 12.04.01 LTS to 18.04 64 but LTS
211
Can I skip over releases when upgrading?
67481
How to revert a do-release-upgrade?
24165
Upgrade to version newer than repositories
35093
Upgrading from the command line?
119595
Is it necessary to upgrade to 14.04 LTS or can I stand in 12.04 LTS forever with no problem?
127766
how to upgrade my Debian package with minor changes
7580
How to safely upgrade from an older Ubuntu version to a newer one?
35243
Is it safe to do-release-upgrade from 12.04.4 to 14.04.1?
129223
Ubuntu upgrade from 17.04 to 18.04
88901
Updates for Ubuntu LTS Desktop versus LTS Server
110148
Why does `do-release-upgrade` skip a version?
66915
How to request a package upgrade in the next Ubuntu release
60659
Install newer package version from trusty-backports
157183
Upgrading LTS to LTS (server) -- why wait for the first point release?
109539
How can I perform an offline upgrade using Ubiquity on the installation disc?
31506
How do I update Ubuntu manually?
83107
12.04 continuously offering partial upgrade