Our system expects that QRDA-I files delivered to the P360 portal relate to a specific TIN. Files delivered via SFTP are specifically delivered to a folder named for a specific TIN. Files delivered via drag & drop are specifically uploaded to a specific TIN context.
QRDA-I files can, but typically don't, include a TIN number. QRDA-I files must include an NPI that is provisioned under the TIN to which the file was loaded.
P360 will reject files whose NPI does not match the NPIs provisioned under the TIN. However, there is no way P360 could detect if a QRDA-I file relates to another TIN that the NPI also works for.
Our system expects that all QRDA-I files uploaded relate to the TIN under which the files were uploaded.