Currently the only primary email address associated with the account owner gets billing notices. There is a Billing Notices KB that states otherwise but after my discussion with the support team they are going to update that KB article to remove the reference about sending billing notices to all emails on an account.
My suggestion is to add this feature into the account management settings. It is quite common for there to be a technical account owner and a different person/team responsible for the billing when the account is owned by an organization. Forcing both the technical and accounting/billing emails to a single email address puts all the burden on the customer to sort them from a single email account.
The setting could implemented in the “View Invoice” section of the “Billing & Account” section of the control panel. There would be a simple input field to add an email address to that would receive billing notices. Ideally the notice would include a copy of the invoice.
You could further enhance the feature to have two options:
- get a copy of the billing notice or
- only send billing notices to this email address
If this account is ever removed then the billing notices would automatically revert to the primary email address of the account owner.