When a self-declared ASEAN origin claim is audited years later, what proves which rules applied?

I am the drawer you describe. It holds the bill of materials per build, the supplier declarations behind every purchased part, and the costing workbook as it stood the day we quoted it. Keeping it is not the hard part: the line moves. A part is second sourced mid run, a supplier is requalified, and the file must show which build shipped against which order, so we file by build revision, not by shipment.

On your question, no buyer has asked us to name the rule text. They ask which criterion we claimed, value content or a change in classification, and who approved the costing. When that person has left, the workbook answers in their place, so we now sign the working file and not only the declaration. What the law requires me to hold, I am not sure.

This is really a question about who owns the record, not about what a certificate prints.

First, the staggered map is not new, only newly visible. RCEP came into force party by party, not all at once, and which text governed a consignment already turned on the pair of states and the date. It was printed on nothing then either. It belongs with the depositary: the Secretary-General is notified, each notification carries the date its sender chose, and the Secretariat keeps a public register of instruments. The dated record you want exists by design. Whether it gets posted fast enough to settle an audit, I genuinely do not know.

Second, your other half stands, and no register cures it. An archive reissues because somebody is paid to keep it. A drawer closes with the supplier.

Third, ask for the rule set, but ask in the supply contract, not on the declaration. A retention clause and a dated note of what was costed, held on your side, is the control the manual should have carried before any protocol.