NIW or PERM?

If PERM, your PD should be earlier than Feb, 2007.
Also, if you use H4 then H1, you can only start work from Oct, 2008
(find job before April, 2008 so your employer can apply H1 for you).

I think due to unpredictability of VB, you'd better transfer to F1, and then use CPT or OPT to work until H1B.