I did not select EWS option for my JEE Mains examination but I actually come under EWS, so is there any chance now (19-09-2020) to select EWS option for Jee Advanced?

Hey Krishna,
I think it is not possible to clear it in the form but you can clear this after getting the college of your choice, but the perks you will be going to get with EWS are not applicable for this year but you are eligible for changing this information in your admission form.
I hope my answer cleared your doubt somewhat. Thank you !!