I’m integrating with the FreeAgent API to create daily sales invoices via the Invoices endpoint. I have two questions:
How does the built-in Amazon integration create invoices with a reference like “Amazon Sales 2026-05-22” without it bumping the user’s global invoice sequence? Does the internal integration use a different mechanism than the public API?
When creating an invoice via the public API with a reference field set to a non-numeric string (e.g., “Sales 2026-05-27”), will FreeAgent’s global sequence counter attempt to increment from that value? Or does the counter only follow numeric/auto-sequenced references?
I’m trying to understand whether there’s a way to set a custom reference on an invoice via the API without disturbing the user’s own invoice numbering.
Thanks