H1B to H4 Change of Status

My wife has been working with H4 EAD for a Company and got her H1B thru lottery this year. Her H4 EAD is valid until 2023. She is looking to move jobs and found a new Company who want to recruit her but rejected as they did not want to do H1 Transfer currently.
I found a new job and my H1 transfer is going to be initiated, can I apply for my wife’s H1 to H4 COS and her H4 EAD along with my H1 Transfer application? What happens to her H1 in this scenario? What’s the timeline for the approval in this case?