It is understandable that you are concerned about the category you selected in your JEE Main 2025 application form. Since you have a valid EWS certificate issued after April 1, 2025, you might be able to use it during the counselling process for JoSAA, CSAB, and other state-level admissions, even though you applied under the General category.

While the category you initially selected in the JEE Main application is usually considered final for the result and rank list preparation, there might be a possibility to use your EWS certificate during the counselling stages. When you register for JoSAA or CSAB counselling, you will likely have the option to choose your category again. At that point, you can select EWS and provide the details of your valid certificate.

It's important to note that your JEE Main score and rank will remain under the General category. However, when the counselling authorities allocate seats, they consider the category you choose during registration and the corresponding reservation policies. If your rank falls within the EWS cutoffs for a particular institute and program, you might be offered a seat under the EWS quota.

Therefore, when the registration for JoSAA and other counselling processes begins, make sure to register under the EWS category and provide all the necessary details and a scanned copy of your EWS certificate. The counselling authorities will then verify your certificate during the document verification stage.

Keep in mind that the final decision regarding your eligibility for the EWS quota during counselling rests with the respective counselling authorities and the specific rules they follow. It would be prudent to keep an eye on the official websites of JoSAA, CSAB, and the state counselling bodies for the latest information and guidelines regarding category changes during counselling. You may also consider contacting the JEE Main helpline or the counselling authorities directly to clarify your specific situation.

I hope this helps.