Hello,

No that won't be possible. You have to get your categorical certificate to prove that you belong to a reservation category. To make the certificate, go to your local district office and apply for it.

It won't take much time to make and there is lot of time to counseling. You have make the documents ready prior to counseling process.

If you filled reservation category in your application form then you have to show documents to prove it else your application will get rejected.

Hope it helps!