Change in github auth

We have been using CircleCI for the pandas project for quite some time, and things have been great!

A few weeks ago, starting just after this build. We started receiving this message:

Your build was not run - reason code (:github-failure).

see the latest builds.

but ONLY on PRs that I think are from contributors that are not following CircleCI (this is a guess). Mine and the other devs PR’s work just fine (as well as the master branch).

I just flipped the remaining switch to On from Off on the Advanced Settings, which was the Pass secrets to builds from forked pull requests option.

Any ideas what changed / happened?

thanks
Jeff