I am working with both our vendor and internal teams to identify and resolve the issue. While I cannot get into the specifics, please know it is something I am staying on top of.
I'm keeping my fingers crossed on one hand right now, and I hope we'll see the results soon --- so that I won't have to include my other hand...
I was just feeling lucky so thought I'd chance my arm and try to login directly to the community, and lo and behold it worked!
As noted in a few other threads, I can confirm that the login issue is resolved on the Community as you have seen. Our teams were waiting to ensure that the fix was stable and sustainable in production before publishing that the issue was fully resolved.
Please continue to let us know if you run into any other issues.