Planning
On this page you will find information to guide your planning activities for the MHHS Programme.
Baselined MHHS Implementation Timeline
At the Programme Steering Group (PSG) on 8 June 2023, Change Request 022 (CR022) was approved following Ofgem’s approval of Level 1 milestone changes. PSG agreed that version 5.0 of the MHHS Programme Plan would be adopted as the baseline change.
The below Plan on a Page (PoaP) is the Baselined MHHS Implementation Timeline that articulates the delivery stages of the Programme. Click on the image below to open an enlarged version.
Please note: This is the baselined plan from CR022 in 2023. This is being updated following Ofgem's decision on CR055 on 29 November 2024.
Delivery of the MHHS Programme is phased: there are three defining critical paths to starting migration:
- Systems Integration Testing (SIT) Minimum Viable Cohort (MVC), who participate in SIT and qualify via the Qualification Assessment Document (QAD) process to reach the earliest migration start Critical Path 1 (CP1). Other SIT Programme participants can Go-Live between Critical Path 2 (CP2) and Critical Path 3 (CP3).
- Participants who do not participate in SIT but reach early migration via Tranche 1 of Qualification (CP3).
- Other participants will pursue the Qualification route (in later tranches).
You can find more information on the Baselined Plan, Milestone Register and Implementation Approach on the Programme Plan & Complementary Documents page of this website.
Key information to support your navigation of the Programme
Which deliverables are out for review and what are key dates that I need to be aware of?
The Participant Checklist (previously the Master Consultation Dashboard) is a checklist to keep Programme participants up to date with Programme requests for review and engagement.
You can view the checklist below:
What are the Programme governance meetings that I need to attend and where can I find information on them?
Visit the Events page of this website
Where can I find information on the Critical Path my organisation is on regarding Testing and Qualification responsibilities?
- If you are non-SIT participant: view the document below:
Non-Sit Supplier Journey through the MHHS Programme
- If you are participating in SIT: visit the SIT page of this website
- If you need more information on Pre-Integration Testing (PIT): visit the PIT page of this website
- If you are Placing Reliance: visit the Testing Overview page of this website
If you have any questions, or would like further information on this, please email [email protected]
Elexon's Assurance of changes that all Market participants must make for Milestone 8
The MHHS Programme will introduce changes to Legacy Market participants to support the Migration of Metering System Identifiers (MSIDs) from legacy arrangements to MHHS and vice-versa (Reverse Migration). Reverse migration can take place during the migration period where a customer migrated into the MHHS arrangements switches to a Supplier that is not yet MHHS Qualified.
These changes are set out in design documentation in the MHHS Programme’s Migration Design, which will be drafted into the Balancing and Settlement Code (BSC) through the delivery of the MHHS Programme Code Artefacts. These Code Artefacts will come into force under the BSC at the Programme's Milestone 8 (M8) on 7 March 2025, and therefore all Market participants will need to have made changes to support MHHS Migration Design by M8. There are no obligations on these legacy participants to qualify as part of the MHHS Programme activities. Therefore, Elexon will use its existing Performance Assurance activities to assure that these “legacy side” changes to participant processes are complete.
Please note that these are the BSC Performance Assurance Techniques and the Retail Energy Code (REC) will also apply Performance Assurance Techniques under the REC Performance Assurance Framework to assess readiness from a REC perspective. For more information on the Code Bodies activity in this area, please view the Qualification Approach & Plan.
What does this mean?
Elexon issued an Assurance Information Request (AIR) to all Market participants that are not Qualifying under the new MHHS arrangements. This ensures that they have the correct provisions in place to support MSID migration and reverse migration ahead of the 2025/26 Performance Assurance Operating Period (PAOP). Elexon will present the AIR findings and recommendations to the Performance Assurance Board (PAB) for approval, after which the findings will be presented to the Qualification Advisory Group (QAG) and the Qualification Working Group.
This AIR acts as a Request for Information (RFI), as an assurance tool, and will help Elexon to understand how a certain process or Party operates. After every AIR, Elexon will provide an update on the findings and any proposed next steps for further risk management recommendations. This could lead to further analysis, providing additional support, or to deploy any other Performance Assurance Techniques (PATs), as needed.
Elexon will also use Technical Assurance checks and the BSC Audit to assure that participants meet their BSC obligations post-implementation. Where participants fail to meet their obligations, Elexon will deploy the Error and Failure Resolution (EFR) technique.
Elexon is also aware that risk to Settlement within the 2024/25 PAOP could be significantly increased by Market Participants focusing on preparing for the new arrangements. Elexon will continue to review and edit the Risk Operating Plan (ROP) as required throughout the PAOP.
These are the current arrangements agreed by the PAB, and this view may be revised. For further information on these arrangements please see the public papers from the April 2023 PAB meeting.
For more information on this update, please email [email protected]