This incident has been resolved.

A workaround was deployed (you might notice that GitHub repositories are sorted differently in the "import new projects" view)

We identified an issue with GitHub's `/orgs/:org/repos` API when combined with the `sort` parameter, and reported it to GitHub's support. We are looking now into deploying a temporary workaround.

We are seeing an elevated rate of 502 errors from the GitHub API used to list user repositories