回复：再问小白兔:H1-B question, Thanks again.

Usually in cases like yours, better file premium processing, so that you know your verdict on COS in two weeks. If USCIS approves your COS (in addition to the H1 approval) by issuing a new H1 I-94, you are fine. otherwise, you go abroad for visa stamp. If regular process and if COS rejection that comes after you start working or long overstay, it hurts you chance for a visa stamp.