The provisions of this act as to apportionment of cost and the issuance of bonds and the levy of taxes shall apply in all cases where the improvement of a highway had been petitioned for under the provision of Laws 1909, chapter 201 [*], but which projects had not been completed nor the cost thereof apportioned prior to the taking effect of this act. This act shall apply to petitions heretofore signed, but not filed or granted, under the provisions of the said laws repealed by this act.