The deployment schedule is not quite that simple. If you open the 'Included in' section of the breaking commit, you can see it was included in wmf/1.26wmf21. According to https://www.mediawiki.org/wiki/MediaWiki_1.26/Roadmap that was deployed to mediawiki.org, zero.wikimedia.org and some test wikis on the 1st, most wikis on the 2nd, and then only Wikipedias on the 3rd.