Topic: CHANGE OF VISA STATUS FROM F3 TP F1

Dear Members, I am a petitioner for my daughter, PD 21 april 2008, she was married therefore here status was F3 when I filed. Unfortunately her husband died in a car accident. I called NVC and was told that I need to send them a copy of the death certificate which I did on July 8, 2014, but I still have not heard anything from NVC how long does it take them to reply back or how much time it takes to process the change from F3 to F1. Also, since her status would change so would here cut off date too? Thank you