H1-B EXTENSION & AMENDMENT

[Sandy16]

Hi,

My scenario: I am on stem OPT,  in march my LCA is approved for state - A with client-X and H1-B application is pending. Mean while in September I got new job opportunity in state- B with client -Y and started working at Client -Y at state B. While I am working at client-Y my H1-B is approved. My employer did not filed for amendment and now its time for filing H1-B extension. I am filing for H1-B extension and amendment with client Y at state -B.

My question: After filing extension, if USCIS contacts HR or manager at my current client-Y for verification my information from when I am working at client -B and HR respond to them that I am working since September. If I have RFE, how can you work at client-Y since September when your H1-B application is approved with client - X at state -A

In this scenario how I can file H1-B extension to get approved ? 

It would be helpful to know if anyone of you faced such situation. 

Really appreciate for your help.

Thank You,

Sandy