Hello Chef Friends,
Over the years, we have evolved as a business along with GitHub. They have added a number of features to their platform, making it easier for companies and open source users to manage permissions to give the right people access, and identify when people are no longer participating.
As such, I've been working to tidy up our GitHub organizations to simplify user management and bring our permissions in line with these features. This week, I identified a number of teams with users that didn't have any repositories, or were otherwise completely inactive for at least the past year, and have removed those teams and users.
If you were one of the affected members, please do not fret. We still love you and value your contribution, and we understand if you've been away for a while. I encourage you to see our OSS practices documentation and reach out if you're still interested in contributing. 
If you have any questions or concerns, please reach out to me directly, joshua@chef.io or @jtimberman on Twitter and the Chef Community Slack.