do-release-upgrade - Could not determine the upgrade
1520
How to install software or upgrade from an old unsupported release?
100494
Update Manager asking me to update kernel but apt-get upgrade does not?
67481
How to revert a do-release-upgrade?
111573
What's the best way to re-enable PPAs/repos after an upgrade?
107792
Update information outdated, "Failed to fetch cdrom"
66915
How to request a package upgrade in the next Ubuntu release
118978
Not all updates can be installed: partial upgrade
134080
Still can't upgrade? Is there a new delay?
77692
How do I update Drush to the latest available version?
41964
Where is the update to 14.04.1 in update-manager?
129101
Upgrading Ubuntu 9.04 to 9.10 when Update Manager doesn't let you
11873
How to check an OS update is complete?
12578
How do I upgrade to a newer version of Ubuntu?
123413
Will apt-get dist-upgrade upgrade my system to a newer version?
89856
How to resume the interrupted upgrade from 14.10 to 15.04?
43236
Should I upgrade when a development branch becomes stable?
140850
Why does do-release-upgrade on Xubuntu running version 18.04 not offer to update to 20.04.1?