H1b Extension during first year of H1

[vmand2]

Hi,

Wish you all Happy New Year

My First H1b Expires on Dec 2013 and i am eligible to apply for an extension from june/july 2013

1.Can i apply for extension even before Jun/July (i.e) right now?

2.I have'nt got my stamping done for my first H1b (came in on F1),If i get my stamping done in the next month and my H1b extension is approved in july or august ,Can i go out of the country any time until dec 2013 without my 2nd H1b stamping as my 1st H1b is valid until Dec 2013 or just because my extension is approved ,should i get stamping done even if i have time until dec 2013

Please advice

Thanks in advance