Hope you are doing good.
You need to understand that during the counselling procedure the officials only e confirm that the credentials you mentioned in the application form are correct or not. The details you mentioned in the application form are the ones which are checked during the counselling procedure.
You mentioned that you uploaded your OC certificate, but now you want to upload your E W S certificate. You should email the concerning authority about this, this will serve two purposes. First that you will get a confirmation that yes you can do this and second that while the counselling procedure if your pws category certificate creates of problem you can show to the authorities.
Please email the concerning authorities about this.
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