Separate the Hold Invoice Field from the Method of Invoice Delivery:email, fax, etc
The function of this field causes issues when you have a customer that wants to be bill ship complete (C) but also wants invoices emailed to them as well as statements. This field needs to be dedicated to one or the other because it can't do both.
You can do this already by using the Use Email or Fax flag in the OE2 tab of the customer screen. https://support.ecisolutions.com/doc-ddms/help/customer/In_the_Customer_Order_Entry_Tab.htm