NIT Calicut has some of the most illogical rules regarding branch change, some of these include:
As a result of this ridiculous policy, a more deserving candidate fails to change his branch. For example, someone with CGPA 9 could not change his branch because he was the 3rd topper of his branch while someone with a CGPA 8.8 can change his branch if he is the topper of his branch.
So, branch change at NIT Calicut depends a lot on your CGPA and obviously your luck!