Due to the 2020.02.29 CAA Rechecking Bug 5.1k, we unfortunately need to revoke many Let's Encrypt TLS/SSL certificates. We are e-mailing affected subscribers for whom we have contact information
This post and thread will collect answers to frequently asked questions about this revocation, and how to avoid problems by renewing affected certificates early. If you are affected, please: thoroughly read this thread, and search the community forum, for an answer to your question.
Read the full thing at https://community.letsencrypt.org/t/revoking-certain-certificates-on-march-4/114864