L1B to H1B COS and travel to India

I am working on L1B extension in company A and petition validity till July 2014.Company B wants to process my H1B through COS in April 1st 2013.Now I want to travel India due to unavoidable reason, plan to go 2nd week of March and comeback on 2nd week of April.But Company B says applying 2nd week of April too late and quota may be over by that time and suggests to apply I have to available in US by April 1st.

Now my question is after applying H1B COS, can I travel India without losing my H1 COS.
What is the best time to travel, before H1B COS approval or after but before 1st Oct 2013.

If I travel after the COS approval but before 1st Oct then can I reenter with my L1 visa and does that affect my H1B status?

During India travel Is it require to go for H1B stamping as my H1B will be effective from 1st Oct 2013.

Appreciate your help on these queries

  1. It is advised not to travel during the COS is under processing.

  2. If you can travel prior to filling COS well and good. Otherwise you should wait for COS to be approved and then travel. Best case would be to get the COS done under premium processing, get the approval and then leave the country.

  3. Yes you can enter on L1 in this case. Your H1 status would start from October 1. Till that time you are on L1 and can freely move in or out of the country using your L1

  4. No you do not need to go for stamping because you intend to enter back on your L1 before October 1