As a manufacturer, you set the rules on one side and follow someone else’s on the other. Your suppliers must send acknowledgments, ASNs and invoices that meet your requirements. Your EDI customers must send orders your ERP can process. And the retailers and distributors you sell to hold you to their own vendor compliance requirements for orders, ASNs, labels and invoices.
Often each of these is managed separately. Supplier testing happens by email in the procurement team, customer testing happens in the EDI team, and retail requirements are handled by whoever owns that account. Nobody sees the whole picture until a rejected document or a chargeback arrives.