Can someone participate in spot counselling for the WBJEE, if he/she had already selected one in round 1, 2 or 3?

No matter whether you had been alotted with seat in 1st/2nd/3rd round of counselling or not, or you had taken admission in some college based on your seat allotment during usual counselling, you are always eligible for the spot round. Student who has participated in counselling but didnt get any seat, or instead of getting a seat didnt took admission or got a seat and took admission at respective college, all are equally eligible for Spot counselling . Just keep in track of announcement of dates.