I wouldn’t count on that as long as there is no support agreement between Nextcloud and Univention.
The Nextcloud app for UCS in Univention App Center is based on the latest release from the Nextcloud stable update channel. Major releases are typically provided in the stable update channel within 3-6 month after release. The app will then also receive an update in the App Center.
Probably they watch a wrong file or API to know when there is a new release available via stable update channel. Nextcloud 23 definitely is since a while.
Since there are no “inline” updates in UCS-Nextcoud, Nextcloud still remains at the latest official release 21.0.7-0.
As long as the UCS app-store hast no more recent version, all installations remain at that release.
As a user you probably don’t need to be worried about using an unmaintained software. For enterprise and service providers Nextcloud does offer under some subscriptions limited maintenance for older versions of Nextcloud that are no longer community supported. When they will upgrade is not something anyone on this forum can answer, the Univention sysadmins are responsible for that.
Hey, I took your concern internally and disussed it with our director of engineering, Andy, and he confirmed that you are right and that our team is responsible for doing the upgrades, and that they are scheduled. Sorry for the noice
Today I have seen, that Nexcloud 23 for Univention server 4.4 and 5 is available now. One user reported that after update a warning appeared:
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