H1B to F1 change of status

[DrJackofalltrades]

Hello,

I am currently on a H1B valid till 2014, and I intend to pursue a PhD starting Fall 2013. School should reopen around middle of August 2013.

I inquired my school's international affairs, and they told me they can apply for a change of status.

Lets say (example) they apply for change of status on March 4th 2013, and I get the approval notice on May 20th 2013 , I understand my H1B 'can' terminate that day, and I am already on 'F1'.

My questions are

1) Can I remain employed 2 weeks after I get the approval notice (since I am already on F1)?
2) Do I need to leave the country until school reopens (middle of August)?

Would appreciate your inputs..

Thanks!!