You should have gotten two additional emails, for the CE edition. You'll see a new "Digital Rights" key, this will be used to 'upgrade' your previously early access code to the CE edition. In order to do this, log into the square enix account management, click on Select service -> FFXIV. This will launch a "new" looking account interface, click ACCOUNT SERVICES ->add the code (new) that you received in the email. It should only be 4 letters long for each box.