Cap gap rules

[iyers]

If a person is on F1 visa and gets sponsored for H1 which gets filed in time and approved, then can he start work prior to October 1 considering he is not eligible for an OPT? What are the cap-gap rules?

[vroni]

if the person is not eligible for OPT the cap gap rule does not apply.
the cap gap rule is as follows:
1) if a person is on OPT on April 2 and a H1B1 petition has been filed (and start date for H1B1 is October 1), then the person can continue to work on OPT until either the H1B1 petition gets denied or the H1B1 visa kicks in.
2) if a person is in the 60 day grace period after OPT on April 2 and a H1B1 petition has been filed (and start date for H1B1 is October 1), then the persons F1 status is extended until either H1B1 is denied or starts October 1. in this case the person can remain in the US but is not allowed to work.

[hireitpeople]

If a person is on F1 visa and gets sponsored for H1 which gets filed in time and approved, then can he start work prior to October 1 considering he is not eligible for an OPT? What are the cap-gap rules?

You may not work prior to October 01 - See excerpts from USCIS Site
How does "Cap-Gap" Occur?

An employer may not file, and USCIS may not accept, an H-1B petition submitted earlier than six months in advance of the date of actual need for the beneficiary's services or training. As a result, the earliest date that an employer can file an H-1B petition is April 1, for the following fiscal year, starting October 1. If USCIS approves the H-1B petition and the accompanying change-of-status request, the earliest date that the student may start the approved H-1B employment is October 1. Consequently, F-1 students who do not qualify for a cap gap extension, and whose periods of authorized stay expires before October 1, are required to leave the United States, apply for an H-1B visa at a consular post abroad, and then seek readmission to the United States in H-1B status, for the dates reflected on the approved H-1B petition.