in 2018.3, if you update the bill type of the component bill's bill via bill maintenance, it updates all bill detail records' bill type where it is used as a component. This behavior can be verified by viewing BM_BillDetail in DFDM and making and reverting the bill type for a given sub-assembly. So you might be able to accomplish this with a VI job with a source file containing the bill twice, and only import into BM_BillHeader, you should only need the minimum required fields and then the BM_BillHeader.BillType field. In the source file, the first record for a bill can have a bill type value for maybe I or E, just to make sure it is changed at least once, and then the second record for a bill can have the intended value for the bill type. Haven't tested this but in theory, it should do what you need it to.