373. Where, in exercise of powers conferred by the Order, the undertaker acquires any interest in land in which any apparatus owned by NTL, NTR or NTLL is placed and such apparatus is to be relocated, extended, removed or altered in any way, no relocation, extension, removal or alteration shall take place until NTL, NTR or NTLL (as the case may be) has approved contingency arrangements in order to conduct its operations, such approval not to be unreasonably withheld or delayed.