An SSL certificate can only be renewed within 30 days of the expiration date, so you will not have the option to renew your certificate if the expiration date is more than 30 days out.
If you try and bypass the 30-day renewal window by purchasing a new SSL certificate, it will give you an error message if you try to put it on the same domain name.
You also cannot renew an SSL Certificate if it is not setup. In order for us to complete the SSL renewal it needs to have completed the setup process and not be cancelled.