The Joint Admission and Matriculation Board has directed and advised all 2017 UTME candidates to ensure that they do not change to any institution that its Post-UTME registration deadline has passed or an institution that has already commenced or concluded its Post-UTME screening exercise for 2017/2018 academic session.
This means that candidates who wish to change their institution can only change to a school that is yet to conduct its Post-UTME screening exercise for 2017/2018 academic session.
Once the school you wish to change to has commenced its Post-UTME screening exercise, it is advisable not to change to that school.
The reason for this is that if you change to an institution that has already concluded its Post-UTME screening registration or has conducted its Post-UTME screening exercise, it is likely that the school must have downloaded the final list of candidates that applied to it from JAMB database which means that your name will not be on the list an as such, you do not stand a chance to of being considered for admission in that school.
So if you must change your institution, change to one that its Post-UTME registration is still on. As a matter of fact, I advise you make such change at least days before the Post-UTME registration deadline.