Details:

H1B Issue Date (Company-A) : Nov 14 2008 
Expiration Date : Jul 20, 2011
Entered US on : Jan 24, 2010
Quits job : May 5, 2011
and Leaving US : May 15, 2011
Planning to switch to H4 : Sep XX, 2011

Questions:

* After quitting the job, how long do we have to pack and leave the country?

* With expired first-H1 from company-A(Jul 2011), what happens when we apply for H4 to H1 transfer for company-B in Jan 2012?. Is the new extension still considered cap-limit exempt?