currently i am in US on H4 status,and my h1B is approved last year when i was in india and i didn't go for H1B stamping till now.Also i have both H1 & H4 with the same company A.Some company B is offering me a job now.

1)Is it possible to apply COS(H4 to H1B) and H1B transfer at the same time through company B? And Is this transfer possible with out stamping of H1B(which is with company A)?

2)Instead of all this can i file a new H1B with company B, and will this H1B comes under the quota? If this process is a success from when can i start my work.

3)As i am in valid h4 status what can be the success rate of this COS (described above)?

Kindly explain in detail.

Thanks