terminal will not allow upgrade of 1604 lts
728
Unable to lock the administration directory (/var/lib/dpkg/) is another process using it?
11556
Can I smoothly upgrade from one LTS to next LTS release?
24165
Upgrade to version newer than repositories
64509
Can't update from official repositories [Error 409]
105335
How do I upgrade my Ubuntu server from one LTS version to another? Is this safe?
23302
How do I install/upgrade r-base to the latest version?
46424
Cannot update software center repositories
31506
How do I update Ubuntu manually?
19288
Update manager doesn't offer an upgrade to the new release
100494
Update Manager asking me to update kernel but apt-get upgrade does not?
56150
Can't upgrade/update ubuntu 18.04 as apt/dpkg error is showing up
144172
How to upgrade to a point release from the same base release (12.04 to 12.04.03)
146117
Update locked within terminal
9901
How to upgrade from 18.10 to 19.10, using the command line?
50810
No upgrade available for 19.04 from 18.10
58979
How can I upgrade Ubuntu LTS to the next one offline?
87236
How to upgrade Ubuntu 12.04 to 13.10?