Hello ..Danish..

Well it is a big issue. You only submit your category i.e in your application form. On the basis of that your cutoff are formed, you are shortlisted or not is totally depend on that. So it is one of the important factors in councelling. 

You not allowed to change your category at the time of councelling or before it. Your selection are take place on the basis of the category you wrote in your application form. 

Good luck...

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