The MHHS M8 REC Release will be implemented on 22 September 2025. M8 is the milestone where the MHHS code changes go live across all impacted industry codes – REC, BSC, and DCUSA. For REC Parties, this means new obligations, updated schedules, and changes to how data is handled and shared.
The two major Change Proposals that are being implemented as part of this REC Release are R0209 – Implementation of Market-wide Half Hourly Settlement (MHHS) Arrangements and R0241 – MHHS Incremental Changes for go live.
Additionally, these Category 3 Change Proposals will be implemented on 22 September 2025 inline with the MHHS M8 Milestone:
- C3-0136 – MHHS Metering Guidance. This proposal implements new metering guidance documents created to support Parties with understanding systems and processes updated for the new MHHS arrangements.
- C3-0137 – Guidance on Electricity Metering Points – MHHS. This proposal is to implement the new Guidance on Electricity Metering Points – MHHS document.
- C3-0138 – EES DAM – MHHS Update. This proposal is to implement an updated Electricity Enquiry Service Data Access Matrix, which captures the permissions approved for new user categories and new data items under MHHS.