SSL notification clarity
Standard SSL Notifications as are follows:
Your server's SSL certificate for cpanel will expire in less than 30 days.
You need to install a new certificate as soon as possible. You can install a
new certificate using WHM's "Manage Service SSL Certificates" interface:
Service Configuration >> Manage Service SSL Certificates).
This should clarify that if the SSL is self signed, that it will be automaticlly renewed by cPanel and no further action is necessary.