This field contains a comma-separated list. This list may contain:
-- the text "invoice" indicating emails should only be sent to contact_email
- addresses with the invoice_dest flag set
-- the text "message" indicating emails should only be sent to contact_email
- addresses with the message_dest flag set
+- the text "invoice" indicating contacts with invoice_dest flag should
+ be included
+- the text "message" indicating contacts with message_dest flag should
+ be included
- numbers representing classnum id values for email contact classes.
If any classnum are present, emails should only be sent to contact_email
addresses where contact_email.classnum contains one of these classes.