4. CHANGE PROCESS
4.1. Either party may serve a Change Notice proposing a Change and such Change Notice shall be processed in accordance with the following sections of this Change Protocol:
(a) an Authority Change to the Facility and/or the Services or the Facility which is a Low Value Change shall be processed in accordance with Part 2 (Low Value Change) of this Change Protocol;
(b) an Authority Change to the Facility and/or the Services which is a Medium Value Change shall be processed in accordance with Part 3 (Medium Value Change) of this Change Protocol;
(c) an Authority Change to the Facility and/or the Services which is a High Value Change shall be processed in accordance with Part 4 of this Change Protocol;
(d) a Contractor Change to the Works, and/or Facility and/or the Services shall be processed in accordance with Part 5 of this Change Protocol.
(e) an Authority Change during relating to the period prior to the Services Commencement Date shall be processed in accordance with Part 6 of this Change Protocol.