Hi Abhishek,
If you don't get your desired college in round 2 of the WBJEE Counselling, do wait till Round 3. However, if you still do not get what you want, the college you received in Round 1 will still be available that is unless you have upgraded to a better college as per your priority list. Downgrading is not available in WBJEE Counselling and if you are not satisfied with the college at hand after Round 3, you can choose to opt out of counselling.
Hope this helped.
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