Hello aspirant,

As per your query, if you have registered under general category in session 1 then you have to register as a fresh candidate in session 2 for changing it as OBC category. If you register as a session 1 candidate in session 2 then you will not be allowed to do any changes in the details and documents (like examination centre, income certificate, caste certificate, email address, etc) of session 1 registration. So you must do registration as a fresh candidate in session 2. One thing you have to know is that for session 2 you to use different contact number and email address from what you have registered in session 1. If don't then you might face any kind of technical issue at the time of registration. To avoid these issues do the same.

Hope this helps you:)