Hello Aspirant,

The seat allotment is a mock seat allotment and the results of actual seat allotment is different.First of all seat allotment depends on various factors such as no. of students participating, no. of seats left.The results of mock seat allotment is different as compared to the actual rounds.By the end of the special round you will the actual college that comes well within your rank.Usually previous year's cut-offs give you a good idea about the cut-off but that isn't necessarily accurate as the factors vary as per the situation.

You can use the college predictor tool to  see which colleges you have chance at,

https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

Hope this helps

Regards