The 1.36.0-wmf.1 version of MediaWiki is no longer blocked[0].
The new version is deployed to all groups[1]. Thanks to everyone who helped unblock the train!
-- Your humble train trawler
[0]. https://phabricator.wikimedia.org/T257969 [1]. https://versions.toolforge.org/
wikitech-l@lists.wikimedia.org