In the Billing Address Form there is a field to select which address to use: Customer Address or Billing Address. If the E-Mail field above it is populated with an e-mail address. Regardless of which billing address you choose. The Invoice/Statement will go to the e-mail address listed in the Billing Address Form. It would seem more logical to have the Invoice/Statement go to the default e-mail or override e-mail address if the Option "Bill Customer Address" is selected.
I get the intent, but it doesn't matter which option we choose. If we choose Bill Customer Address, it bills the Billing Address. If we choose Bill Billing Address, it bills the billing address. Why have 2 options if they both produce the same result?