FBDI for invoices does not derive data from the PO when any Tax information is filled in?

Summary:

Hello Team

We have a scenario at the client where invoices were loaded via FBDI with a purchase order, additionally the Transaction Business Category and Intended Use fields were filled in, which were not in the PO. During the invoice conference at AP, we observed that the tax fields such as Product Fiscal Classification and Product type were not derived from the PO.
In another test, we filled in the FBDI with the PO, but no Tax data. In this scenario, the information that was filled in the PO was derived.

We have the following questions:
When we are uploading invoices via FBDI, do we have to fill in all the tax data, regardless of whether they are in the PO?