Product: Transaction Manager
So, let's say you have a Trading Partner that has multiple stores, and one of those stores sent a paper Purchase Order. Can you send an EDI 810 Invoice in response? The short answer: yes, it's possible.
However (yes, there's a however), you always want to communicate this with the Trading Partner. If a paper PO was sent, a paper Invoice might need to be sent in response.
Rule of thumb: always communicate with your Trading Partner.