Can I Upgrade an Existing Deluxe/SSL Certificate to a Premium SSL Certificate?
If you want to upgrade an existing SSL certificate to a Premium SSL certificate, the existing and future certificate must be purchased in the same account to avoid having to revoke the active Standard or Deluxe SSL for the domain in question.
If the same certificate common name exists in an active status in a different shopper account, you will not be able to request a new certificate. The first one must be revoked before a new one can be issued.