H1B transfer while extension is in progress

I am working with employer A and my H1B extension is in progress regular mode (was filed with USCIS on 30th Dec 2019 and My I94 expired on 10th Jan 2020).

  1. Is it possible to change employer when my extension petition is in progress?
  2. what happens if my current extension petition gets rejected and transfer petition still awaits response from USCIS.

Thanks in advance!!