H-1B Visa

1. I am a F-1 student graduating in May 2021. An employer "X" wants to e-register me for the H1B lottery and I am hoping for a better offer from employer "Y". Suppose I got selected in the H1B lottery filed by "X". Can I start working for employer "Y"? What are my options to work for employer "Y"?

2. Can employer "Y" file my H1B petition even though I was registered in the lottery by "X"?

3. Can I ask "X" to not file an H1B petition after winning the lottery and use F1-opt as work authorization?

4. I am also applying for F1-OPT. Can I use my F1-opt to work till September for "Y" and then use H1B in October to work for "Y" while it was filed by employer "X"? I believe "X" would send an H1B petition with change of status.

I'm currently on H1-B visa. I applied for I-485 in October 2020 and I got my EAD/AP card approved. I'm in EB2 category with priority date of March 2011.

I was convicted for DUI in November 2011 and consulted Rajeev Khanna Sir in 2012 through 15 minutes telephone consultation. As Rajeev sir advised, I got the certified copy of court disposition and a letter from criminal lawyer explaining that this is a misdemeanor -- quoting the statute.

So with the first time DUI arrest (in 2011 been 10 years) , I have 2 questions:
1) I would like to know if first time DUI affects my chances of getting I-485 approval?
2) I'm planning to convert from my H1-B status and start using EAD, will it be wise to do that considering the DUI arrest.
 

I am currently on H1B visa (3rd year) and a few days back I got my I-140 approved in EB-2 category. I want to know if I can change my employer and retain my priority date.

I am on H-1B & my wife also on H-1B. After three months pregnancy leave my wife is planning not to work and to transfer from H-1B to H-4. She will not have last paychecks copy for three months so will it be an issue during transfer? Will she need to start the job again to get three paychecks copy ?