You can only change if you are considered as active full time student and not otherwise. The logic is, you have data that thousands of students will be attending certain programs/ University in certain Provinces and they eventually change to cheaper colleges somewhere else.. to IRCC, that was a loophole and they introduced that guidelines. Each provinces have occupation in demand policies and policy maker take into consideration admissions data from the DLIs across province. I hope i tried answering “logic” concern