M10/M11 Cutover Plan

The M10/M11 Cutover Plan sets out the activities that MHHS participants will be required to carry out in the lead up to M10, at M10, and between M10 and M11 to enable the Programme to successfully reach both M10 and M11 respectively. It outlines what these activities are along with when they are expected to take place, who the responsible parties are, the declaration requirements that participants will be expected to follow and the key dependencies that may impact particular activities.   

The updated M10/M11 Cutover Plan was taken to the Migration & Cutover Advisory Group for re-baselining on Tuesday 1 April 2025 and confirmed for approval. You can view the baselined artefacts below:

M10/M11 Cutover Plan v1.1

M10/M11 Cutover Delivery Plan v1.1

M10 Acceptance Criteria v1.1

If you have any questions, please email the Transition & Operational Readiness team at OpReadiness@mhhsprogramme.co.uk 

Participant Cutover Plans

As detailed through the Transition & Operational Readiness Working Group (TORWG), the Programme has requested that Central Parties, Licensed Distribution System Operators (LDSOs), Systems Integration Testing (SIT) Suppliers and SIT Agents share a Cutover Plan with the Programme.

These plans should outline the technical cutover activities that each participant must undertake to ensure that their systems are fully deployed, operational, and compliant with the M10/M11 Cutover Plan deadlines, enabling the Programme to successfully meet both the M10 and M11 milestones.

To assist with this, the Programme has developed templates for each constituent group (listed below) that we require to share a response, outlining the key requirements that must be included in their plans along with the relevant activities from the Programme Cutover plan that will need to be referenced within individual plans. 

• LDSOs
• SIT Suppliers
• SIT Agents
• Central Parties

You can view the respective templates in the libraries below.

What are the timescales?

Central Parties were required to submit their Cutover Plans and completed templates by Friday 16 May 2025. 

LDSOs, SIT Suppliers, and SIT Agents were required to submit their Cutover Plans and completed templates by Friday 30 May 2025. 

Additionally, LDSOs, SIT Suppliers and SIT Agents will need to submit an updated plan and template following the publication of the consolidated Programme M10/M11 Cutover Plan, and validate that their plan aligns with the consolidated Plan, which will be published in mid-June. This update from participants is expected by Friday 27 June 2025.

To support this activity, the Programme will organise walkthrough sessions with Programme participants, on a constituency basis, to run through the requirements and answer any participant questions. 

We'll also set up workshops to run through the request with each Central Party and discuss the requirements within their templates.

Please submit all plans and templates to Opreadiness@mhhsprogramme.co.uk 

If you have any questions, please also email Opreadiness@mhhsprogramme.co.uk