Sec. 4. When the state board of finance has designated a depository for public funds, the treasurer of state shall accept the application of the financial institution to act as a depository for public funds. A designation under this section expires only under the following conditions:
(1) The board of depositories revokes the status of the financial institution as a depository under section 6 of this chapter.
(2) The financial institution resigns as a depository under section 7 of this chapter.
(3) Another law terminates the depository status of the financial institution.