Ideally, 30 minutes weekly that are reserved. I have pinged @greg and and emailed him to this effect. We currently have a backlog of upstream things we want to get locally here, and that doesn't even include our completely local stuff like Sprint.
- panel in the homepage including the time of the next known upgrade
- general information at mw:Phabricator - https://www.mediawiki.org/wiki/Phabricator#Weekly_update_.2F_maintenance_window
- one-time announcement to wikitech-l and engineering
- informative HTML page to be used when Phabricator is down