Where is that upgrade section?
Wow, yeah, all references to the upgrade section are broken since January 2015. You are the first one to note this. I believe that this is what you are looking for. Cheers
Hmm, or probably this page. The docu appears to be a bit chaotic right now. :| Will have to redo all of this from scratch.
So the general setup of instructions seems to be sorted out now. However, will have a look into the pages to see if fluff is needed.
That one doesn't seem to say anything about updating the composer.local.json file with a newer version before running update. Would that actually update anything? I have been using mediawiki/semantic-media-wiki": "*", to just get the newest available, but I feel kind of reckless about that, and besides, the earlier part of the page doesn't actually suggest that. Let me know if I should just add it - I would have done the edit if I was sure.
Hmm, the docu links to Help:Upgrade and there you have a list of pages depending from where you start your update/upgrade like e.g. Help:Upgrade/Upgrade_from_SMW_2.5_or_later_and_MW_1.25_or_later
