I wanted to know if an employer is filing a H1B petition on April 1, 2014 for a F1 student who has STEM OPT valid till July 2015, if the H1B petition is selected in the lottery, is it possible to have the H1B start date (change in status from F1 to H1B) after October 1, 2014 like in Dec 1, 2014 or Feb 15, 2015 so that the student can use the remaining days of his OPT ? If its possible, when it should be done like during the filing of H1B petition, the employer has to mention a start date, can a later date be provided after Oct 1, 2014 or can the start date be changed after the H1B petition is approved ?