Possiblity with move Non-profit H1B to profit H1B

Hi I am currently working full-time in LA on Non-profit h1b. yesterday, in second lottery, my h1 was picked for profit company for Tesla Client. this is in master quota. So what should I do here?

1> What is concurrent H1b and is it applicable in my case? Pros and Cons?

2> If yes, will I be able to go back to my previous employer if my H1b gets rejected.

3> Do I have to work part-time with only one employer or both of them? If with only one employer, which one?

4> Both the employers are in different cities. If USCIS comes to visit the location, how should I handle it?