Put ISO 20022 cover payment (pacs.008 + pacs.009 COV) back in order

THE DRILL AS TEXT

1. In ISO 20022 cover payment (pacs.008 + pacs.009 COV), what happens first, and what follows?
   • The debtor initiates the cross-border payment — A corporate treasury sends a pain.001 with structured party and remittance data. The same starting point as a serial payment — what differs is how Bank Alfa routes the instruction and the money.
   • Bank Alfa validates, screens, and debits — After checks and screening on the structured fields, the customer account is debited and the bank chooses the cover method: announce directly to the creditor agent, and fund through correspondents.
   • The pacs.008 goes directly to Cassia — The creditor agent learns the full payment details immediately — who is paying whom, how much, and why — carried in structured fields under a Business Application Header. But this message alone brings no money.
   • The cover transfer goes to the correspondent — The pacs.009 COV moves the money along the account chain. Its underlying-customer block repeats the debtor and creditor so every bank in the chain can screen the real parties, and it shares the same UETR as the pacs.008.
   • Meridian settles the cover across its books — As in the serial flow, settlement is a book transfer between the two banks' USD accounts held at Meridian, the shared correspondent.
   • Cassia sees the cover arrive on its nostro — A credit notification tells Cassia the money side is complete on its account at Meridian. Now it has both halves of the payment: the instruction and the funds.