If your EDI supplier cannot put a station ID of your station into the file they send us we have no way to auto identify the invoice as to which station it belongs to (Coremark as an example does this and the invoices are sent to us during the night and we auto process them so they are in the station database by morning). The only choice we have is that the invoice must be sent from the station to which it belongs using the S2k client.
To set this up you need to make certain that the S2k client is setup with the correct directory and that any invoice that you receive is manually stored in that directory. As soon as S2k detects the saving of that invoice in that directory, s2k will send it to the web and process it. The progress can normally be monitored on the client.