einvoice-preflight's FatturaPA rules were written from memory of the schema and tested only on hand-built files. This run pointed them at 15 real samples: the Agenzia delle Entrate's six official ones and nine from eigor.
Most findings were right: the samples use a placeholder partita IVA (01234567890) that fails its check digit, placeholder IBANs fail mod-97, and one official sample's line items sum to 25.00 while its VAT summary says 27.00.
One was ours. IT-018 (element order) flagged the official FPR02 sample because PECDestinatario comes before ContattiTrasmittente, the reverse of the order we had coded. We no longer rank that pair until the XSD is read, with a test. The lesson is the usual one: a rule from memory is a guess until it has met real files. eval/fatturapa-corpus.mjs repeats the run.