H1B transfer with out amendement details

[Mani1254]

I am on a H1B visa valid till Oct 2017 and working for a client through an employer A, and H1B amendment(Change of client and work location) is still in process( I don't even have the receipt number as my employer did not provided it yet) 

Now, I got a good offer from employer B, is it possible to do h1b transfer(while amendment is in process and without knowing the receipt number) using the original I797 which is valid till Oct 2017? Please help

Thanks in Advance,
Much appreciate your responses...