This is a lingering error with the forced logout that some instances did. You can remove and re add your account and it will be fixed or you can wait a few days and we'll get it fixed.
Could you give us a summary of what functions you tend to use, to give us some idea of priorities. I mod here and only ever sticky a post, but other experiences would be useful.
Hi all, if you're getting the spinner when trying to log in, please check that you're using the latest build (0.10.7) by going to https://testflight.apple.com/join/jKENkGjX and following the instructions there.
If you're still having problems after upgrading, please let us know!
Great question, I see it's already been answered for you, but I've also added a stickied post with details of the latest changes.