I am architecting an integration with the Amazon Selling Partner API (SP-API) to automate invoicing and accounting sync with an ERP. I need to retrieve the Buyer's Tax/Billing Address for tax compliance.

I am aware that Amazon is introducing major changes to the Orders API recently in 2026, specifically with the launch of the new Orders API v2026-01-01 which consolidates data and deprecates legacy v0 operations.

However, looking at the documentation for this new v2026-01-01 version (under the "Get tax information" tutorial), it states that the field Order.tax.taxRegistrations[].taxRegistrationAddress is explicitly restricted:

"Each buyer registration can return the following fields: [...] taxRegistrationAddress — buyer's business address (Türkiye only)"

Right now, I do not have the restricted roles approved on my developer profile (like Tax Invoicing or Tax Remittance) because I want to make sure I am applying for the right permissions and using the correct architecture before requesting them from Amazon.

Merchant sellers operating in the EU (Spain, Germany, Italy, etc.) or North America strictly need the legal billing address to generate lawful tax invoices, so there must be a way to obtain it.

My Questions:

1. Is the new 2026 Orders API completely useless for billing addresses outside of Türkiye? If I obtain the Tax Invoicing (Restricted) role, will the taxRegistrationAddress field unlock for EU/US orders, or is it hardcoded by Amazon to only return data for Türkiye?

2. What is the correct path for non-Türkiye marketplaces in 2026? If the Orders API cannot provide global billing addresses due to PII limitations, what is the exact Report Type (reportType) in the Reports API that provides this data? (e.g., Is GET_FLAT_FILE_ORDER_REPORT_DATA_INVOICING still the standard way in 2026?)

Any guidance from developers who have successfully automated global invoicing with the latest SP-API updates would be highly appreciated.