Fees are tied to grade levels, which makes sense.  In our scenario, we have siblings that started the year at different grade levels.  A fee was assigned to the older child. Mid-year, the other child switched to the sibling's level and needed to be assigned those fees, but they weren't available since they were already used by the sibling.  When two siblings are the same level at the beginning of the year, the fees are available to each of them; they should be available later as well.