We have now upgraded the SSL certificate with a new certificate from Letsencrypt. This certificate will auto-renew every three months. This is now automated and should not again expire like we have had today.
We have reverted to StartCom due to some issues with some clients complaining about the certificate, but we will test again soon. Just now we are back to StartCom for Ejabberd. On the website we still use Letsencrypt.