This seems to be the case - another comment in this thread links to https://stripe.com/docs/security/data-migrations/exports https://stripe.com/docs/security/da

This seems to be the case - another comment in this thread links to https://stripe.com/docs/security/data-migrations/exports https://stripe.com/docs/security/data-migrations/exports, which appears to suggest that the data is exchanged to another PCI-DSS provider via PGP-encrypted JSON-dump. That JSON-dump includes the card number, expiry, and billing address.