3.—(1) The authorised development must not commence until a construction phasing scheme for the authorised development has been submitted to and approved in writing by the relevant planning authorities. The phasing scheme must set out the sequence of construction of the authorised development and under which requirements approvals are to be sought in whole or in part depending on the contents of the construction phasing scheme.
(2) Where a construction phasing scheme has been submitted to and approved by the relevant planning authorities, the details to be submitted to the relevant planning authorities to discharge any requirement may relate to a particular construction phase only, in order that the construction or operation of that phase may commence in accordance with the approved details for that phase alone. Where details have not been submitted in relation to any particular construction phase, then construction of that phase must not commence until the relevant part of any requirement has been discharged in relation to that phase. Construction must then be carried out in accordance with any relevant approval.