need to extend non immigrant visa?

[unique1231]

i have filed I -130 and I -485 through marriage to US citizen on March 2011, biometric was done on May. My visitor visa B1/B2 will be expired on Aug 2011, so what i have to do to maintain my stay before i get approval? do i need to extend non immigrant visa? how long usually takes to get approval?

[svaradara]

You can file an I-539 (fee is $290) to whichsoever USCIS Service Centre covers the place you are staying.