Can I go from H4 to H1B (H1B > 6 years, have approved I -140 from previous employer)

I am on h1B for more than 6 years and have an approved I-140 from my previous employer. My current employer also filed for perm and currently my I-140 is pending for 2 months. My question is - if I move to h4, can I convert back to h1B later? What are the rules for converting from h4 to h1b.

Typically, you can EXTEND H1 status using an approved labor(+year after approval) OR with an approved i140. But since you have moved to another H status(H4 already), you can not EXTEND H1 status. Rather you will be under COS(change of status) from H4 to H1. This cant be done officially but I have seen few cases approved. I would suggest you to try COS while you are on H4. If the COS fails, you still can continue to stay in H4.

Thanks for the reply. You said you have seen few cases approved, how was this possible if it is not officially possible.

Gray area. You may most likely be able to renew it. If you want, you can try it.