From the article:
Moving to the Fediverse
This tension between these communities and their host have, again, fueled more interest in the Fediverse as a decentralized refuge. A social network built on an open protocol can afford some host-agnosticism, and allow communities to persist even if individual hosts fail or start to abuse their power. Unfortunately, discussions of Reddit-like fediverse services Lemmy and Kbin on Reddit were colored by paranoia after the company banned users and subreddits related to these projects (reportedly due to “spam”). While these accounts and subreddits have been reinstated, the potential for censorship around such projects has made a Reddit exodus feel more urgently necessary, as we saw last fall when Twitter cracked down on discussions of its Fediverse-alternative, Mastodon.
It's a program called GH Campus Experts. It used to be on the GH education page, but now it seems like it's been hidden behind a few pages and a new domain. From what I can tell, it's basically just events, hackathons, workshops, etc. that are run by GitHub. I swear I remember it being more than that, but maybe I'm just misremembering stuff.