The update check in LibreOffice only offers updates within the same codeline, 4.x users will be offered only 4.x updates, 5.x users only 5.x updates.
Only if the micro version (the third digit of an available fresh version) is larger or equal the micro version of the installed still version will the user be offered the fresh version:
installed still | available fresh | available still
x.y.z | x'.y'.f | x.y'.s
f >= z → fresh update will be offered
f < z and x.y'.s newer than x.y.z → still update will be offered
otherwise the response will be "up to date/no update available"
however it is unlikely to ever reach the f >= z condition with the release schedule when a user regularly updates.
Only when a new major version will be new fresh/the still version is replaced by another codeline will the user see the update.
of course the user should not be bothered with a "update is available" notification in the toolbar when it is a cross-version update (as likely the user has a reason to use the old version and probably doesn't want to update) - but for a manually triggered update, the response should indicate the availability of a newer fresh version.
→ thus the result should still be "no update available", but the result string should point to new version.
If done this way, also no changes to LO itself are necessary.
Setting to NEW.
Some thoughts about automatic update suggestions:
As said before, particularly the procedure is not clear, if a new feature release (fresh version) has been published and if the still version is still current. To my opinion in this case it's not possible to suggest for each user the suitable version. Some like to update to the more sophisticated version (still) and others like to update to a version with new features (fresh). See also bug 84122 and bug 93282.
I think the only way to get rid of this problem is to offer both updates so that a user can decide. In order to help users in their decision target groups for the different versions can be displayed. E.g.:
Versions x.y.0 - x.y.2: "Experienced LibreOffice users, which like to use new features. Innovative user who are willing to report bugs to the Document Foundation."
Versions x.y.3 - x.y.5: "Basically suitable for all users. Users which set a great value upon stability should use versions x.y.6 or x.y.7."
Versions x.y.6 - x.y.7: "For all users suitable. Particulary for users which set a great value upon stability and do not need the most recent features."
Another problem may be the period of the update check. By default the period is set to 'Every week'. This can be changed to daily or monthly in the options. I think a lot of users could be annoyed if they get every week a message that there is a new version available. And I don't believe that all users know the possibility to switch off the messages in the options. Perhaps these users are absolutely satisfied if they get a new version every year and in the meantime LibreOffice is running hopefully without any problems and without any update messages.
Hence also longer periods for the update check should be available, e.g. every half year and every year. Furthermore the user should determine the period of the update check without looking into the options dialogue. This can be done e.g. with a welcome message, when a user starts LibreOffice the first time after the initial and each update installation. E.g.:
"Thank you for installing LibreOffice version X.Y.Y. ...
LibreOffice will be continuously enhanced. Shall LibreOffice check and inform you, if there are updates available? [Yes|No].
Every Day , Every week , ..., Every year "
*** Bug 84122 has been marked as a duplicate of this bug. ***