Believe it or not. I procastinated my update of certbot (ACME2) like about 4 month now. This evening I pulled all my enthusiasm to finally update... did a dry-run. No success. WTF??! Looking up and down... searched problem on my end... just to find out: ha! it's not me.
OK. I'll wait. And check
https://letsencrypt.status.io/You rock!