Is it possible to edit my listing's product type using Selling Partner API

I have submitted product data using the Selling Partner API's XML Feed. The products are uploaded with the Product Data set to "Office / Office Products" and a Browse Node 201097031 (Stationery & Office Supplies > Calendars, Planners & Personal Organisers > Wall Calendars).

This is giving me the 8541 error because the Product Type "Office Product" does not match the pre-existing items' type "Calendar". I cannot see a way to change the XML feed to set the product type to Calendar, it is not a known type in the XSD definition files.

Nor do I see a way I can correct this value using the SP-API patch request. The product type does not seem to the an editable attribute in the JSON feeds.

How else might I be able to correct the product type on my listing?