After the effective date of suspension, the operation of the commission shall be concluded and any and all funds remaining held by the commission and not required to defray the expenses of concluding and terminating operations of the commission shall be returned on a pro rata basis to all persons from whom assessments were collected in the immediately preceding marketing year. However, if the commission finds that the amounts so returnable are so small as to make impractical the computation and remitting of the pro rata refund to these persons, any funds remaining after payment of all expenses of winding up and terminating operations shall be withdrawn from the approved depository and paid to the University of California for continued research on dates. If no such program exists, the funds shall be paid into the State Treasury as unclaimed trust funds.