It's important to keep your income up to date so that the amount of your funding is accurate. Otherwise, if there is a discrepancy with the amount on file and the amount we get from Canada Revenue Agency (CRA), your funding could be recalculated. You could end up with an overpayment that has to be repaid or be restricted from getting OSAP.
You'll be able to update your income about a month before the start of your second term. For most students, this will happen in late fall. Instructions will be sent to you at that time.