Dear aspirant,
Yes , there is a difference between the opening and closing ranks of josaa. In the first and 2nd round you will find a little difference and the next four round upto round 6 , you won't find any difference specially in high cut off colleges.
For more information you can check out the link given below-
https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer
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