If for any reason you need to change your email address you can do so by going to into your Account page. You will see an input to put in your new email address. Make sure you double check before saving. You will need to log back in using your new email address.
If the new email address is already associated with a free account all your collections and onepagers will move to that account.
If the new address is already associated with a premium account all of your collections and onepagers will NOT move to that account and must contact support for the transfer.