Job Switch during November to April.

Hello everyone, I have found out recently that most IT companies in India (based in and out of India), mostly hire Software Engineers only during the months of November to April. They don't hire much for the rest of the year.

Is this true? Please advise. I have a total of 4 years of experience and I am planning on switching, but, it seems like if I don't put the papers before April, I won't be able to find a good job later on.

Consider the service based companies and the Big 4 companies.