Visitor visa extension pending but I-94 expiring soon

[smartthinker]

Hello

On behalf of my mom, I applied for her visitor visa extension on 2nd of February 2012. Her I-94 expires on 26th of March, 2012. (6-month stay)

1. Can she just stay in the US even after the I-94 expires if she doesn't get any decision?
2. If extension is accepted that's good. If denied, in how many days should she return back to the homeland?

Thanks a bunch in advance

[peace999]

Yes she is legal till the response comes. If it is a denial she is considered out of status
immediately because her original I-94 has expired. She must leave asap within a reasonable few days. There is no immigration check at departure but the returned I-94 at departure will record an overstay in the USCIS system.
The next time she enters US on the same visa, she must carry a proof of extension denial
and proof of the date she departed ( Indian arrival stamp on her passport or boarding passes).
Because if there is a query about overstay it can be overcome by the proof.

This is the reason , extension apps if elective should be filed as soon as possible , so the response can be received before the I-94 expires.