(a) In all cases where land theretofore platted into lots and blocks has been returned to acreage under the order of the county court in which the land lies and where the return to acreage did not involve the closing of any public road or thoroughfare, the action of the court in ordering the land returned to acreage and in cancelling or annulling the platting of the lands into lots and blocks is validated and affirmed.
(b) The provisions of this section shall not apply to any lands lying within the corporate limits of any town or city, nor shall it affect the title to any lands but shall merely validate the conversion of the lands from lots and blocks into acreage.