So, nextcloud version 15.0.x is out already and whenever you are logging into your next cloud with your administrator account, you still get this "you are on the latest version" message.
Further more, you just got a update to version 14.0.x while waiting for version 15.0.x.
To fix this, all you have to do is to switch from the channel "stable" to "beta". After a page reload, you should see a version 15.0.x available. Do the upgrade and do not forget to switch back to the stable channel.
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