Whether we would allow a student to retake the end of year 1 exam depends on the student's circumstances. If there are genuine reasons (i.e. a medical condition, we would need a doctor's note ) for a student to underperform we would let the student retake the exam as soon as they are feeling better. We would also change their grade in that instance.
If a student majorly underperformed because they had a really bad day or were overly stressed out and as a result they got a much lower grade in comparison to their performance so far, we would first need to speak to the subject teacher and the student's DPC or SBC regarding the possibility of the exam retake. If they think it would be beneficial for the student to retake the exam as a learning experience and they are willing to assist the student again with that we would allow the student to retake the exam.
In that instance, however, the grade will not be changed and will remain the same as the one achieved in the first exam.