Can I work at my old company even with expired i797 and I94, if I have a pending H1b transfer?

Hi guys,

so here is my situation: I’ve been working for company A for 3 years and my first 3 years will go expire on 8/22/2022. I haven’t filed H1b extension yet, because I find company B who is going to file H1b transfer for me (prob in Jul). I am kinda confident I can get the receipt before the expiration date, but not sure if I get a RFE after it, can I still work at company A without an extension? Thank you!

You can’t work for company A unless they file extension of status.