means:
(a) an access undertaking given to the Commission; or
(b) a request made to the Commission for the withdrawal or variation of an access undertaking; or
(ba) a request made to the Commission under subsection 44ZZAAB(7) to consent to the revocation or variation of a fixed principle included as a term of an access undertaking; or
(c) an application under subsection 44ZZBB(1) for an extension of the period for which an access undertaking is in operation.