Sch NINTH para 1
If in the administrative county of London or in any borough or urban district, or in any parish in a rural district, the undertakers have power to take under the enabling Act dwellings occupied by thirty or more persons, the undertakers shall not enter on any such dwellings in that county, borough, urban district, or parish, until the Minister has either approved of a housing scheme under this Schedule or has decided that such a scheme is not necessary. For the purpose of determining for the purposes of this Schedule, the number of persons by whom any dwellings are occupied, any occupation on or after the fifteenth day of December next before the passing of the enabling Act, or, in the case of land acquired compulsorily under a general Act without the authority of an order, next before the date of the application to the Minister under this Schedule, for his approval of or decision with respect to a housing scheme, shall be taken into consideration.