Credit assignment by the public administration (PA) requires:
Explicit acceptance by the PA (need to on-board the list of one or more Signatories from the Buyers).
The form of a public deed or private contract between the parties, authenticated by a public notary (Gayadeed may be inlcude signature by a public notary - can this be a PAdES-T signature?))
eInvoice Acceptanceby the Buyer via SDI is
Optional
May arrive within 15 days from the delivery
In case the acceptance ntification isn't produced by the Buyer, the SDI automatically notifies the supplier with a meet of the deadline notificatoin
eInvoice explicit Acceptance Deadline expiration does not determine implicit acceptance of the debt by the PA
Supplier-side signature powers: how to determine them automatically (Chamber of Commerce "Infocamere" API)
Buyer-side signature powers: how to determine them automatically? (API Infocamere?)
How to prevent double spending of the invoice (Air protocol + optional "Notes" field of the electronic invoice containing references (did) to the NFT smart contract for the supplier in question)