A county's increased RATA funds for a project program period shall correspondingly reduce the limit of RATA funds that may be allocated to the county in the next project program period; provided that the county road administration board may grant a county's request to decrease such a reduction by the total amount of increased but unexpended RATA funds.

All reductions and reduction adjustments as described shall be effective in the project program period following the period in which the increase in the RATA funds is approved.