Greetings!
I have a question regarding H-1B transfer for which I thought you could provide me some clarification.

I am currently in US on H-1B. I was working for my previous employer till Jan-2014 and started working for my new employer from Feb-2014. Currently, I have a H1 visa stamp from my old employer which is valid till Sept-2014. My new employer has filed for my transfer and have the receipt notice (petition is not approved yet, it is in RFE under premium processing). Now, we have a team conference in Paris-France next week from 11-Feb-2014 and my new employer wants me to attend the conference (will return on 16-Feb-2014).
1. Is it advisable to travel outside US in this circumstance?
2. When I return back to US on 16-Feb-2014, I will be holding a visa stamp from my old employer (valid till Sep-2014) and the receipt notice of my new employer for the transfer which is in progress (RFE under premium processing). Will this be sufficient to re-enter US on 16-Feb-2014?
3. At the port of entry, what should be my answer when the officer asks "Who is my employer" and what should be the supporting documents that I should be carrying?

Thanks in advance for your response.