Whenever the director of the department of finance believes it to be for the best interest of the unsecured depositors and creditors of any bank that any proposed plan for maintaining or restoring the solvency of such bank, or for effecting any merger or reorganization thereof, should be carried out and made effective,the director shall issue his certificate of approval, and thereupon all other unsecured depositors and unsecured creditors of such bank shall be held to be subject to the agreement and plan so approved by the director and all depositors and creditors shall be bound thereby and their deposits and claims shall be subject thereto to the same extent and effect as if they had joined in the execution thereof, and their deposits and claims shall be paid in the manner provided in the plan so approved, as aforesaid, and not otherwise.