H4 to H1B COS and travel before H1B start date

Hi Anil

I had applied for my H4 and H4 EAD extension in July 2021 under NPT ( previous H4 and EAD extension was rejected because by husband switched jobs and the old company revoked the H1B) but considering the long delay and 180 day overstay rule after the rejection letter I travelled to India in November 2021 and got a new H4 stamp. I came back to US on January 2022 on H4 and sent USCIS my updated i94 to just process my existing EAD extension application with new i94.
Meanwhile, on February 4th my H4 to H1B COS was approved in premium processing with start date as May 16,2022.
My question is :

  1. Can I travel to India in April and get back before May 7th on H4 and then the COS automatically comes into effect on May 16th?
  2. Or should I get a H1B stamped if I travel and get back before May 7th 2022.
  3. Also should I withdraw my H4 EAD extension application now that I received H1B approval notice? Considering the last action rule.
    Thank you

Yes.

Not really required.

No need. If your EAD is approved, you can use it if you switch back to H4 in future and if the EAD is still valid at that time. You already paid fpr EAD application so why would you withdraw. Even if the EAD is approved after your COS to H1B, it does not impact your H1B status.