It is not uncommon for this to happen. It is also not uncommon for a version of a device to pass emissions, being modified during the testing process to do so,

It is not uncommon for this to happen. It is also not uncommon for a version of a device to pass emissions, being modified during the testing process to do so, but those changes never make it back into the production BOM. Or if they do, the production build is never re-qualified.