Where this Part of this Schedule applies in relation to a highway, the statutory undertakers whose apparatus is under, in, upon, over, along or across the highway have the same powers and rights in respect of that apparatus, subject to the provisions of this Schedule, as if the order authorising the highway to be stopped up or diverted had not been made or, as the case may be, as if the conveyance of land pursuant to section 256 of this Act had not been made.