A school bus may be used to transport any student who lives within the mileage limit, if a mileage limit has been established by a local board of education, and if: The school bus is not filled to capacity; No additional bus stop is added to the route to transport the student; and The transportation officer or his designee has identified a specific existing hardship that would justify allowing the student to be transported. The transportation allocation of a county may not be reduced because of compliance with this section.