Can I travel to India before OCTOBER if my H1 got approved in may itself?

My H1 got picked up in lottery, I am planning to file premium processing. If my H1 get approved in May itself
I have the following the questions

  1. Can I travel to India in May and come back after OCT with stamping(because it’s my first H1, So it will start on Oct 1st only)
  2. How many months can I stay outside USA, Is there any time period ?
  3. Can I go for stamping before OCT ?

Note: I can’t come back before oct 1st because I don’t have a valid visa stamp on my passport.

@Anil_Gupta Can you please answer this