hello there

i think you may have little confusion . the jee advanced admit cards are released now so you cannot change anything .further te category you have mentioned in your jee mains will remains same for your advanced and you cannot change it . however you will be considered as a general candidate if you unable to submit your certificate at the time of the counselling .checkout faqs on jee advanced

https://jeeadv.ac.in/faqs.php

best of luck