H1 Extension got RFEed, but have different approved I-129

Hi All,

Hope everyone is good. I have some doubts with my US working. I am currently working for Employer A, and have approved I-140. My I-94 got expired in April’2018, but the Employer A filed H1 Extension in Feb’2018 itself. So i am currently in 240 days grace period. In mid of July i got the offer from Employer B, and they filed H1 transfer as well. And it got approved a week ago.

The USCIS decision on Employer A was still pending, and today, it got RFE’ed. Hopefully in another 10-12 days, i will get the reason for RFE. I have few questions in this regard. Can you please answer/suggest me on this.

Is it legal to join Employer B, when the first case is still pending?If i join Employer B, what will happen to my H1 extension of Employer A? Will it get revoked by my employer, without providing the RFE documents? If so, will it impact me in future (Like new I-140 processing with Employer B, Stamping, etc)Employer B is OK with delaying couple of weeks in joining date. But getting the status update from USCIS might take 2 months of time (as per my employer A), which may not be feasible with Employer B. What is the best suggestion you can give me, in this situation?Thanks All in advance.