H-4 COS and H-4 EAD Processing Time and Effective Date

Hello Admin,

I am currently working for a cap-exempt employer on H-1B visa and am planning to apply for H-4 COS and H-4 EAD with my spouse’s H-1B extension (expires in Sept’20) this month. I would really appreciate your help with the following questions regarding H-4/H-4 EAD effective date -

  1. Does it have to be after the effective date of her H-1B renewal (Sept’20)?
  2. My current H-1B is valid until March’22 and would like to continue working for the current employer upon H-4 EAD approval. Considering current processing time for H-4 and H-4 EAD, which effective date makes the most sense to avoid any lapse in my employment authorization?
  3. My PERM is pending right now and I-140 will be filed in April’20 with premium processing. Does H-4 COS effective date affect it in any way?

Thank you for your help in advance.