Hi,
My in-laws visitor visa is expiring on on Dec 23 2010 and we have booked tickets for them on Dec 21 2010.Due to my father-in-law's health conditions we wanted to extend his stay for another 1-2 month .Since my mom-in-law is a dependent , we wanted to apply for extension of visa for my father-in-law and put my mom-in-law as a supplement applicant.

1. Their I-94 is going to expire in 6 days and iam planning to do E-Filing(to get the receipt immediately) and send documents in mail separately ..Would there any problems if we do E-Filing with 6days remaining

2. If their extension gets denied we are planning to book tickets within 15 days from denial .Will their 10 year visa become void OR is there a chance of them being denied at port of entry if they come back in 2012 ?.