Change of Status for H1b Visa Holder After Being Laid Off

[James1102]

On March 19, 2012 I was laid off from my company, and was told my H1b will be revoked. Immediately following my termination of work, I filed a COS to F2. However, the USCIS receipt came back just yesterday (April 16) and says the I-539 application was not received until April 9. So my questions are:

1) Am I legal to stay in the U.S. during the this pending period? Or I am already an illegal immigrant since the termination of work was before the filing date of I539?

2) Will the delay of receiving the documents to USCIS negatively affect my application?

3) If the case is approved, do I need to leave U.S. and come back to activate my status?

4) What are the chances of this case not being approved by USCIS?

Thank you very much for your help!

[Mr. Knowitall]

Is the USCIS in agreement as to when the I-539 was mailed?