H4 to H1 wit EAD

I have a question related to my case and your help is much appreciated.
I was on H1B VISA and was in USA for 6 years till Dec 2018. My I-140 was approved however an extension beyond 6 years could not be filed due to short time left on my H1B and I had to leave USA. Currently I am in India, and my employer has filed a cap-exempt H1B petition from India, due to premium processing on-hold, it can’t be processed any faster.
My spouse is on H1B and I can apply for H4 with EAD to be able to work in USA. Could you please help me understand, if I apply for H4 with EAD and travel to USA, while my cap-exempt H1B is in-progress, what will be the next step? Once my H1B petition is approved can I start working or there is a different process to come back on H1B. Thank you for your help !

  1. you can enter into US at any time on H4 visa while your spouse’s H1 is valid. Then apply for EAD, start working.
  2. H4 is a visa to enter into US and live legally. EAD is an add-on WORK PERMIT(NOT a VISA) which allows you to work in US. It requires you to be on H4 visa in the united states.
  3. While you are working on H4-EAD class, if your pending H1B gets approved, you will lose both your H4 status(thus EAD permit also lost) and you will be automatically in the H1B status. Thus, you must start working on H1B visa from its approval date.

Thank you so much for your response. Could you please help me understand if there needs to be a COS filed for H4 to H1 by my H1B employer while in USA? Since, I will be on H4 status, can I start working once H1B gets approved or do I need to get my H1B VISA stamped before start working on H1B? Thank you in advance !