There are 2 types of cut offs. Qualifying cut off and Admission cut off. The qualifying cut off is published by NTA and JOSAA will release the admission cut off. Qualifying cut off is for Candidates who want to apply for JEE Advanced. Those Candidates who meet the qualifying cut off only will be eligible to apply for JEE Advanced. The admission cut off is the minimum marks that are required for possible chances of seat allotment to a particular College or Institution. Cut offs are determined by the total no.of seats available, Difficulty of the exam, previous year cut off trends, no.of Candidates appearing for the exam and no.of Candidates applying for a course. Now the cut offs will decrease if the no.of seats available are higher and vice versa. The postponement of the exam has no bearing over the cut offs. But yes, if the Candidates really put up a good show in the exams as in if the students perform real good and the no.of available seats are lesser than the no. of Candidates qualified, the cut offs increase. You can prepare for JEE Mains by using our JEE Knockout package: https://learn.careers360.com/knockout-jee-main-april/