H1B Transfer during Cap-Gap?

[newy0rker]

I am currently working for Employer A. I have 3 layers - My Employer > Vendor > End Client & I am on a long contract. My H1B approved in April 2013 only & that will start from Oct 2013. My OPT will expire in July. I am going to get Cap-Gap from my university through my current H1B copy.

 

Now, I wan to join Another Employer  B because they're ready to pay me more. (Vendor & End Client will be the same that I am currently working with, I have already confirmed with the vendor and they're ready to work with my new employer).

 

So,

 

1. would it be possible to transfer my H1B with employer B?

2. If yes to 1, Can I start working with my new employer before Oct 2013? ( I am planning to do in Premium Processing - So I am hoping to get my H1B tranfer approved by mid July)

3. Most important question, what are the risks/chances to get H1B transfer denied.

I would appreciate your help. Please guide me!!!