Warning: Do not upgrade to 24.04 yet! There are many instances of systems breaking during the upgrade!
Incidentally, that’s why if you follow the instructions to upgrade you are told there is no new version: there is always a delay while the Ubuntu Team ensures everything goes smoothly.
That said, we have tested upgrades and found them to be successful. What problems are you finding where?
Just to point out a general thing about upgrades as shown in the Ubuntu manual:
Ubuntu users are prompted to upgrade at different times depending on their current release.
Users on interim releases such as Ubuntu 21.10 are prompted to upgrade within a few days of the next Ubuntu release becoming available. This prompt may happen automatically, or when checking for new updates.
Users on a Long Term Supported release such as Ubuntu 20.04 LTS will be prompted to upgrade once the first point release of the following LTS is available. For Ubuntu 22.04 LTS this prompt will appear once Ubuntu 22.04.1 LTS is available.
More specifically about this release, there are similar messages in the announcement:
Users of Ubuntu 23.10 will soon be offered an automatic upgrade to 24.04.
Users of 22.04 LTS will be offered the automatic upgrade when 24.04.1
LTS is released, which is scheduled for the 15th of August.
and the release notes:
Users of Ubuntu 23.10 will be offered an automatic upgrade to 24.04 soon after the release.
Users of 22.04 LTS however will be offered the automatic upgrade when 24.04.1 LTS is released, which is scheduled for the 15th of August.
Looking specifically at the known issues in the release notes, we see:
Upgrades from previous Ubuntu releases are not supported yet. Critical bug fixes for upgrades are expected in the coming days (LP: #2063221 is one example of a critical bug that is difficult to recover from. Please be patient here or make a backup and do a clean install instead.)
It’s possible that the bug mentioned affects some situations more than others, which may be why our tests were successful but perhaps not with others.