Regarding L1 To H1 Status Change and Others

[immihelp]

Hi,
I am currently with Company A on L1 with I-94 valid up to Oct 2009. Company B will be applying for my H1 in April 2007.

1. If my assignment in US with Company A ends in June 2007 and I will go back to India.
Can you please advise me on the following scenarios?
a) If my H1 petition gets approved and Company B applies for change of status,
* Is my L1 Visa is no Longer valid?

2. If my assignment in US with Company A is till Jan 2008 (approximately 1yr)
Can you please advise me on the following scenarios?
a) Since I have applied for H1B, can I continue to work with Company A till my H1B gets approved(approximatel Oct 2007)
b) When I need to get my H1B Stamped?

Also if any other info related to this will be helpful.
Thanks

[immihelp]

1a. It is still valid.
2a. Yes.
2b. Before entering the US again if you leave US.