GH Actions felt so fundamentally janky and under-documented when I last looked at it (October?) that this doesn't come as a surprise. I really can't foresee using it with requirements any stricter than "nice when it works."

Yup, same here. We had periods of more than 8 hours (during Asia daytime / US nighttime) where we couldn't push or pull, which were not mentioned on their status page at all.

I would not be surprised to learn that they have similar procedures to one of my past employers, where exec signoff was needed to even publish an update to the service status dashboard...