Each licensee shall pay over such charity days’ net proceeds to such distributing agent as soon as practicable after the determination thereof, and such agent or agents shall hereafter distribute not less than 90 percent of the aggregate proceeds from charity days’ racing received and available for distribution by it to beneficiaries within 12 calendar months after the last day of the meeting during which such charity days were conducted. The balance, if any, of such aggregate charity days’ net proceeds not distributed within such 12-month period shall be distributed as soon thereafter as is practicable.