H1 Visa Stamping based on current and new petition

[kn]

Hello,

My 6th year on H1 expires on April 21, 2013. I recently got my I-140 approved and my 3 year extension also got approved (starting April 22 2013). My current H1, H1 extension and I-140 approvals are all with the same employer (direct employer). I have to travel to India at the end of Feb and I will be returning back to US by the end of March 2013. My visa has expired and so I will have to go for stamping when I travel to India. I have a couple of questions:

1. Which petition number should I fill in DS-160? I am assuming I have to enter the petition number of the current petition (the one that expires on April 21, 2013)? Is this correct?

2. If I enter the current petition, then can I give the new petition along with my current petition to the interviewing officer? Will they give the 3 year stamping if approved? Or would they not agree and stamp my visa only upto April 21, 2013?

3. If the visa is given only till April 21, 2013 (expiry of the current petition), then would I be able to provide the new petition at the port of entry and request for 3 year I 94? Or will I get the I 94 only till April 21, 2013 (if yes, then it will be problem since I will be entering US on March 30th and will have only about 22 days).

Thanks for your help.

[kn]

Help anyone...