H1b Transfer when outside of INDIA

Hi Team,

I got H1B Visa on 3rd July from Company A. I got new offer from another Company B. Company B about to start H1B transferring process.

  1. What is the duration of Transferring process?

  2. I heard that once transfer process started i will get a receipt number. With this receipt number can i go directly from INDIA to company B place and start working? If yes what type of questions may arise during immigration process.