You need to ask your H1B attorney these questions!
Due to the nature of this forum, I often do not have all the information required to provide legal advice. Accordingly, my responses on Avvo are intended as general and not legal advice.
You are in H4 status if the EOS was granted after H1B COS.
If on H4, you cannot be on H1B. To activate H1B status, you would need to depart the U.S. and enter on an unexpired H1B visa, or ask the employer to file another H1B petition requesting COS from H4 to H1B.
Consult with the employer's immigration attorney.