While kbin.social's site mentioned that they were migrating to a new provider, and as a result, the site might be experiencing some issues, kbin.social has been serving up a similar HTTP 50x errors, and that migration message for well over a month, if not more.
The owner of the site (Ernest, IIRC) has some health issues that have kept him from being as active as he had wanted. He also wrote the frontend code as an alternative to the Lemmy software. Mbin continues onward as a fork of Kbin.
I wish him the best. I hope he gets better. I know too well what chronic illness can do to a person.
In other words, no signs of life. These just point to mbin as the successor, but no mention of updates on the original edition of kbin or regarding kbin's creator..
I was replying to the top comment and adding mbin links for the sake of ease for other users potentially interested in it. I don't know why you expect me to say anything about kbin or ernest, especially when everything about the matter has already been said.