When is the last date for H1B Visa approval?

If USCIS takes 2 - 6 months to approve a petition , does that mean that if you filed a petition in June, it can get approved after Oct as well. I thought that the start date for H1Bs is October 1st. Is there a last date for the consulate to approve th petition?

Yes, you are eligible to enter on or after or 10 earlier to october 1st. There is no last date kind of thing. it may even go to 2013 also.