My site uses 2 custom profile types for a particular set of customers. For these, I have the default billing and shipping profile panes completely removed on the order edit screen via Customer Profile Type UI, yet any edit to an order (manual or programmatic) still re-adds them to the profile on save (resulting in 4 profiles for the order).
The address field has been identified as the culprit, but in my case, the default profile panes are not present in the form, so I don't understand how an address field that isn't there could trigger a new profile being added. Is there another mechanism in Commerce that would add default profiles if they are missing?