Noticed that after mw 1.35.0-wmf.20 to group1 the received logs jumped +1k/s, looks like there's ~10k entries for the message below, every ~5 minutes (I'm assuming due to jobs)
Use of ArticleEditUpdates hook (used in FlaggedRevsHooks::onArticleEditUpdates) was deprecated in MediaWiki 1.35. [Called from Hooks::run in /srv/mediawiki/php-1.35.0-wmf.19/includes/Hooks.php at line 202]
There's a throttle in place at the logstash level for duplicated messages, although it doesn't look like it is kicking in (fully?) in this case: https://logstash.wikimedia.org/goto/d74ea1c87e4f6f7ca96e2fbce43d2e00