I94 Extension for H4 / H4 EAD

Hi AM tech Friends,

My H1B extension approved for 3 years(till 2024). During H1B filing, i have filed H4 for my spouse which is still pending for approval. Later, I filed H4 EAD renewal based on by H1B approval. Since both H4 and H4 EAD are still pending - can we exercise following option to do automatic extension of 180 days

H4 and H4 EAD is valid till Dec 31st 2021

  1. Crossing the border and get the i94 extended based on H1B approval ? if doing so, do i need to file the new H4 and withdraw the old one or interfile cover letter will be enough?

Any clarification will be helpful.TIA

There is no clear guidance from USCIS about it but interfiling should work as per my opinion.