Phases of Admission are depending upon the Qualification rank of the students. For example of there 10000 seats they will call 1st 2000–3000 people during 1st round. Suppose only 1500seats gets filled out then they will call next 3000 ppl. And it goes on till the admissions are done. If you have decided for specific branch try to be above thr last year’s cut off.
All the best.