H4 visa I-94 valid but I-797 is expiring

[niteshtadepalli]

I recently got an H1b amendment filed & approved and my I-797 and I-94 are valid till 09/01/2021. My wife is on H-4 visa and her I-797 and Visa stamp are valid till 07/01/2020 but when we got into the country after an international trip, the officer gave her I-94 valid till 09/01/2021 based on my approved I-797.
* So do we need to apply for her I-539 extension of status as her I-797 is expiring in 6 months? or is having a valid I-94 sufficient?
* Her H-4 EAD is expiring on 07/01/2020 as well. If we are not applying for I-539 extension of status, can she use the valid I-94(till 09/01/2021) to get EAD renewed(I-765)?

[newacct]

1. When you say "her I-797", you probably mean the I-797A approval notice for an I-539 Extension of Status or Change of Status, which came with an I-94. An I-94 is for that stay only, and that status ceased when she left the US. That I-94 is irrelevant after she left the US. When she re-entered, she was admitted on the basis of her visa for a new period with a new I-94 (and she was admitted until the expiration of your H1b petition, as expected). That is her only valid I-94 right now. She remains in status until that I-94 expires, as long as you remain in H1b status.

2. I think so

[niteshtadepalli]

newacct Yes, by I-797 I meant her I-797A approval from filing I-539 extension of status 2 years ago.