Hy,

I would like to answer your query. As per your question, I would like to tell you that the criteria for re-supply exams is not fixed for every colleges and differ from college to college. Generally, it happens that even after getting failed in re-supply exams, there are very less chances that one's academic year is lost. In most of the colleges, it so happens that you are provided some fixed number of chances for giving supply exams e.g. 3 or 4. When all the chances are over, then there is a year leg.

Hope this will solve your query.