The Retail Energy Code Company has published new guidance to support Meter Operator Agents (MOAs) and Suppliers in handling Meter Technical Details (MTDs) for Metering Points that have been reverse migrated from the Advanced Market Segment to Non-Half Hourly (NHH) arrangements.
Background
With the Market-wide Half Hourly Settlement (MHHS) migration underway, all electricity Metering Points are expected to transition to MHHS arrangements by 7 May 2027. During this period, some Metering Points initially operating in the Advanced Market Segment may be reverse migrated—particularly if the new Supplier is not MHHS Qualified. In such cases, the Metering Point can be reallocated to the NHH market, requiring the appointed MOA to provide NHH MTDs, even though only Half Hourly (HH) MTDs may have been received as part of the migration process.
The Reverse Migration Scenario
- Reverse Migration occurs when a Metering Point, previously operating under MHHS Advanced arrangements, is moved back to legacy NHH arrangements.
- The Gaining MOA receives the D0268 ‘Advanced Meter Technical Details’ from the Losing MOA.
- If the new Supplier chooses to operate the Metering Point under NHH (Measurement Class A), the MOA must convert the D0268 into the appropriate NHH market messages:
- D0149 ‘Notification of Mapping Details’
- D0150 ‘Traditional Meter Technical Details’
- D0313 ‘Auxiliary Meter Technical Details’
The Supplier is responsible for informing the Gaining MOA that NHH MTDs are required. Communication methods should be agreed bilaterally, with the D0142 message recommended for requesting changes to the metering system.
Key Guidance for MOAs
- D0149 Creation: Mapping details are not included in the D0268. The incoming NHH MOA should interrogate the Advanced Meter to determine or update the setup. If this is not possible, assume a single rate (SSC 0393) with a single register (TPR = 00001).
- D0150 and D0313 Creation: Most data items can be directly translated from the D0268, but SSC and register details should align with the D0149.
Important Considerations
- Suppliers should carefully consider the risks of converting Advanced Segment Metering Points back to NHH, especially the accuracy of MTD conversion and the need to migrate these sites back to the Advanced MHHS segment before the next milestone.
- Reverse migration of Advanced Metering Points is expected to be rare, as most will not migrate to MHHS until April 2026 or later.
Further Information
New guidance is available on the REC Portal, Population of NHH MTDs when Reverse Migrated from Advanced, to support MOAs and Suppliers in managing this scenario. For more details, visit www.recportal.co.uk or contact enquiries@recmanager.co.uk.