Still does not look right to me... if I create a Sales Order for 3 items... one of those items have Vendor;

NetSuite

as preferred vendor.... but before I fulfill or do anything with the Order the company decide to stop buying from

NetSuite Vendor

and delete it from the Item's Vendors and add a new Vendor:

Oracle

which is now the preferred vendor... Then I can't edit the Sales Order again??? that is far from being right...