Kestrel Dress Rehearsal 2

Kestrel Dress Rehearsal 2 builds on Kestrel Dress Rehearsal 1 by including all participants, not just Suppliers, and demonstrating that Kestrel can support key reporting requirements such as:  

• Plan vs Actual Outturn 
• Aggregated Outturn Reports
• In Dress Rehearsal 2, synthetic data will be used to simulate real-world Migration scenarios. This allows participants to test processes without impacting live operations. 
• Dress Rehearsal 2 also ensures that all participants are familiar with the Kestrel platform, reporting outputs and submission processes ahead of live Migration phases. 

As part of Dress Rehearsal 2, participants are expected to: 

• Access and review simulated reports via the Kestrel portal 
• View their Committed Baseline Schedule and Daily Outturn Reports (Systems Integration Testing (SIT) Suppliers only) 
• Access aggregated baseline schedules and progress reports (Non-SIT Suppliers and all other Programme participants) 
• Familiarise themselves with the test scripts and report schemas ahead of the testing window (all Programme participants)

If you have any questions about Dress Rehearsal 2, please email the Migration team at Migration@mhhsprogramme.co.uk 

Dress Rehearsal (DRH) 2 Mandatory participants 

1. All SIT Suppliers  

• must undertake Sprint Execution activities 
• review synthetic committed Daily Baselined Schedules 
  review Daily Migration Outturn Reports: (RP-04 - Plan vs Actual) and (RP-05 - Transaction Summary) 

2. All SIT Licensed Distribution System Operators (LDSOs) (BUUK & SSEN) and Data Communications Company (DCC) 

• view Aggregate Baselined Schedules 
• review example Aggregate Daily Migration Outturn Reports: (RP-04 - Plan vs Actual) and (RP-05 - Transaction Summary).
  • The Migration team are working to understand if this can be completed in Kestrel and will confirm by the end of August 2025. 

Dress Rehearsal (DRH) 2 Voluntary participants 

1. Non-SIT Suppliers 

• review example of Daily Migration Outturn Reports: (RP-04 - Plan vs Actual) and (RP-05 - Transaction Summary).
  • The Migration team are working to understand if this can be completed in Kestrel and will confirm by the end of August 2025. 

2. All other LDSOs  

• view Aggregate Baselined Schedules 
• review example Aggregate Daily Migration Outturn Reports: (RP-04 - Plan vs Actual) and (RP-05 - Transaction Summary).
  • The Migration team are working to understand if this can be completed in Kestrel and will confirm by the end of August 2025. 

Migration Dress Rehearsal 2 Test Scripts 

The Test Scripts for the upcoming Migration Dress Rehearsal 2 are available below. The test scripts are split into different roles, so please ensure that you complete the correct tab for your organisation. 

Migration Dress Rehearsal 2 Test Scripts

We held a Kestrel Dress Rehearsal 2 Webinar on Wednesday 6 August when the Migration team walked through the test scripts and participant requirements.

You can view the slides and recording from this webinar on the MHHS Webinars & Open Days page of this website.
 
Supplier Agents features 
 Access to Kestrel features for Supplier Agents will not be available for Migration Dress Rehearsal 2. The Migration team are still working to understand Supplier Agent demand and are considering the best way to disseminate this information via Kestrel.

Likewise, Supplier Software providers will only have access to Kestrel for Supplier Group Market Participant Identifiers (MPIDs) where the Suppliers Migration Principal Contact has nominated Software Supplier contacts for Kestrel. 
 
If you have any questions, please email the Migration team at Migration@mhhsprogramme.co.uk   

Kestrel Dress Rehearsal 2 Webinars

Thank you to all participants who joined the Kestrel Dress Rehearsal 2 Webinars on 14 July and 6 August 2025 respectively.

You can view the slides and recording from these sessions on the MHHS Webinars & Open Days page of this website.