Ubuntu has a full two year development cycle, which ends with the release of the LTS system.
The
full development cycle that concluded with the release of Ubuntu 24.04 LTS, started just after the release of the prior LTS (ie. end of April 2022 after Ubuntu 22.04 LTS was released).
During that two year development cycle, it was broken down into four six month cycles, with a
stable release showing the progress. Those
interim or
stable snapshots of where development was up to were viewed by using
- Ubuntu 22.10 (2022-October snapshot released as a stable system)
- Ubuntu 23.04 (2023-April snapshot released as a stable system)
- Ubuntu 23.10 (2023-October snapshot released as a stable system).
- Ubuntu 24.04 LTS or the final result of that two year development cycle.
If you used any
interim release, the only
release-upgrade path you have is to the next release; ie. 22.10->23.04->23.10-.24.04 LTS.
When at the final release of a cycle (ie. 24.04 LTS), you have the choice of staying on that LTS, or upgrading to the next release, which will be first
interim release showing progress towards Ubuntu 26.04 LTS (ie. I'm talking about Ubuntu 24.10).
If you stay on the LTS, you can stay there, and eventually
release-upgrade to the next LTS or final result of next cycle,
after release of Ubuntu 26.04.1 due in mid August 2026.
As stated, installing 23.10 to me makes no sense, given it's purpose as I've outlined, was to show progress towards 24.04 that you can install now! When you're at 24.04, you can stay on the LTS release, or
release-upgrade in time to next cycle & use 24.04 only for six months - it's your choice.