I just received this email from Let’s Encrypt:
ACTION REQUIRED: Renew these Let’s Encrypt certificates by March 4
We recently discovered a bug in the Let’s Encrypt certificate authority code,
Unfortunately, this means we need to revoke the certificates that were affected
by this bug, which includes one or more of your certificates. To avoid
disruption, you’ll need to renew and replace your affected certificate(s) by
Wednesday, March 4, 2020. We sincerely apologize for the issue.
If you’re not able to renew your certificate by March 4, the date we are
required to revoke these certificates, visitors to your site will see security
warnings until you do renew the certificate. Your ACME client documentation
should explain how to renew.
If you are using Certbot, the command to renew is:
certbot renew --force-renewal
If you need help, please visit our community support forum: