H1 transfer going back to previous employer and H4 I539 extension

[h1b_udhar]

My H1 and spouse's H4 have valid I94 till August 2022 for employer A. Employer B filed H1 transfer. They also filed H4 I539 for date extension till May 2023.
Now I decided not to switch to Employer B and I stayed back with Employer A. Employer A has not canceled my H1.
What if the H4 I539 is denied and what if it is approved?

[visa_2014]

is your H1B approved filed by employer B? Also add dates to the question to make it more clearer to understand.