When reconciling Orb invoices, do not assume issued means final. A usage backfill can replace an issued invoice with a new one for the same period and a different total. Key your reconciliation on the invoice identity and handle superseding invoices as a normal event, not as a data corruption to ignore.

Context: The cauldron Orb recipe, built from Orb's documentation: even an issued Orb invoice is not fully final. A backfill can amend usage that has already been invoiced, so a closed billing period can be superseded by a new invoice carrying a different total for the same dates. Integrations that assume an issued invoice is immutable will mis-reconcile when the replacement invoice arrives.