Hi,
My wife currently has H4 visa. She enrolled in Masters and finished for first semester on H4. Now, she wants to convert to F1 visa and we have the following questions:
1) Her current H4 visa (&Visa stamping)is valid till June'2012. University issued I-20 to her. In our trip to India this month, we plan to get her F1 visa stamping done. In the worst case, if her F1 is denied.. wil they cancel her H4 status too ? I'm hoping she can come bck on her current status.

2) Is it mandatory to apply for COS while in US to go for visa stamping ?

Thanks,
Ravi