(a) (Referral of Dispute): Subject to section 11.4(b), any Disputes concerning a Change Response may be referred by either party to expert determination in accordance with clause 48.1 within 20 Business Days of the date Project Co receives the Change Response (or such longer period as is agreed with the non-referring party).
(b) (Other Disputes): Where a party has an express right under a clause to refer a Dispute to the Independent Reviewer for determination or for expert determination in accordance with clause 48.1, that right will prevail over the right to refer a Dispute referred to in section 11.4(a) to expert determination.