The numbers aren’t looking great so far[1]: they’re not cracking 3 9s on their primary service, and their CI/CD isn’t even cracking 2 9s. And these numbers are much better than when I checked a few days ago!
(This should not be read to imply that I think that GitHub’s reliability is acceptable; it clearly isn’t.)
Uptime above 99 I really would only care about the time to get back working. My enterprise experience with Github was multiple days of no work in a year.