This 1973 act is necessary for the immediate preservation of the public peace, health and safety, the support of state government and its existing public institutions and shall take effect immediately: PROVIDED HOWEVER, That each of the provisions of this 1973 act shall be operative and in effect only for employees of those state facilities closed after May 1, 1973 and prior to September 14, 1974: PROVIDED FURTHER, That benefits under section 4(3) of this 1973 act shall be available until September 14, 1975.