[39B. ...
(2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
(3) The Authority must revoke an exemption given in accordance with Article 39A in respect of a [pipe-line] or facility—
(a)if its construction or, as the case may be, the making of the modification to which the exemption relates has not been started within the 2 years beginning with the relevant date; or
(b)if it, or (as the case may be) the modification to which the exemption relates, is not operational within 5 years beginning on the relevant date.
(4) In paragraph (3) “relevant date” means—
(a)if [before IP completion day] the European Commission notified the Authority that it approved the exemption and terms as copied to it under paragraph (1) [(as it then had effect)], the date of that notification;
(b)if [before IP completion day], in accordance with Article 36(9) of the Directive, the European Commission required the Authority to modify the terms, the date of that requirement; or
[(c)if—
(i)before IP completion day the Authority sent the European Commission a copy of the exemption and terms under paragraph (1) (as it then had effect), and
(ii)the European Commission does not act as described in paragraph (a) or (b) before IP completion day,
the date four months after the Authority sent the European Commission a copy of the exemption under paragraph (1) or IP completion day, whichever is the sooner;
(d)if the decision to give the exemption was published under Article 39A(12) on or after IP completion day, the date on which the decision was published under Article 39A(12).]
(5) The Authority may, at any other time, revoke an exemption given in accordance with Article 39A or modify the terms on which such an exemption is given, in respect of a [pipe-line], facility or modification—
(a)in accordance with the provisions of the exemption; or
(b)by giving the owner of the [pipe-line] or facility in question a notice of a revocation at least 4 months before the revocation takes effect.]