Need some important clarifications

[ceherr]

I'm currently in India and my current employer has filed for my H1B. It got picked in the lottery and I have the stamping appointment scheduled in October.

Now, I got another job offer and am going to resign before that date. What will happen to the appointment? Can my employer cancel it?

Do I still have the H1B even if it is not stamped on my passport?

If my new employer wants to transfer the H1B, do they have to go through the lottery again?