15.—(1) Subject to paragraph (2), limit values and target values apply—
(a)from the date specified for each limit value or target value concerned in Schedules 1 or 2, or
(b)when these Regulations come into force, if no date is specified in those Schedules.
(2) Where the European Commission has been notified, in accordance with Article 22 of Directive 2008/50/EC, that conformity with the limit values for nitrogen dioxide in Schedule 1 cannot be achieved by the date specified in paragraph (1) in a particular zone, the date for achieving those limit values in that zone may be postponed by a maximum of five years, provided that—
(a)the Welsh Ministers have prepared an air quality plan for nitrogen dioxide in the zone to which the notification relates in accordance with regulation 20, together with the information listed in Section B of Annex XV to that Directive, and have demonstrated that conformity with the limit values for that pollutant will be achieved in that zone before the date to which the application of those limit values has been postponed, and
(b)the Commission has raised no objections under Article 22 of that Directive to the postponement of the application of those limit values to that later date.