Switching Programme

Providing faster, more reliable switching for consumers

Ofgem launched the Switching Programme to encourage consumers to engage with the same energy market, and to improve their experience of doing so. Its aim to deliver reliable, next day switching for consumers by replacing the existing switching services with a new Centralised Switching Service (CSS).

Welcome to Xoserve’s CSS page. This is the central reference point for our customers on Xoserve’s involvement in, and perspective on, the delivery of Ofgem’s Central Switching Service.

We are committed to keeping our customers fully informed on the delivery of this programme. On a weekly basis, we’ll share our Weekly Progress Report, our Day After Reports (DARs) and our updated view on key risks:

  • Our weekly Switching Programme Status report; this is the weekly report we’re required to submit to the System Integrator, and we’re sharing here for our customers to have the same update
  • Day After Report summaries of key program meetings; these are basic notes that we capture during meetings to share with internal to help with consistent knowledge levels across Xoserve, and to provide a contact point if more information is required. We felt that our customers would benefit from seeing these notes should you wish to understand more about Xoserve’s interactions with the programme.
  • Summaries of the key risks: this is a summarised version of our risk log of topics we believe are affecting the programme and the work that we’re doing to address these risks.

Going forward, we’ll look to widen the information we share based on what our customers are asking to understand. If there are additional updates that you would like, or if you have a comment about any aspect of the programme, please contact Emma Lyndon


CSSC Programme S
ummary: 12th June 2020

As you will be aware the Switching Programme is currently undertaking a re-plan exercise following the decision to delay by up to six months. The SI, DCC and Ofgem aim is to baseline this plan in readiness for approval at September’s delivery group. The SI has committed to include all ESP’s in this re-planning exercise in order to provide the opportunity to feedback and assess against internal plans. We have not yet received a date for this walkthrough but are seeing aspects of the re-plan fed through various programme workgroups, we continue to chase and escalate for a firm date for this walkthrough opportunity in order to provide our input into the re-plan.
I advised in my last update that we have raised an issue with SI with regards to inconsistencies between design documentation, this is particularly prevalent between the physical interface design and the data migration design. The SI has now completed an initial review of the documentation and to date have discovered 22 discrepancies and have confirmed a programme CR is being raised to address the issues. Due to a defect that was identified as part of a data migration smoke testing we have asked the SI to widen this review to include ‘optional’ data items and ‘default’ values.
We are now very much in the testing phases of the project where a number of defects and delays are being seen across SIT external functional testing and data migration testing. SIT functional testing is experiencing delays due to blocking defects. The planned tests for this week will not complete and the SI have confirmed that it is too early to confirm if this will impact the SIT Functional Testing end date. The SI and DCC are rescheduling the test activities and will continue to assess the impact also confirming that there is contingency in the plan to absorb delays to SIT completion and the programme will not take unnecessary risks when creating the revised SIT Functional Testing plan.
Data migration testing started this week, Xoserve are on track with all planned test cases completed to date, however 35% of planned tests have not been executed due to defects with the CSSP. Again, as with SIT Xoserve are concerned that the current DMT schedule is not achievable and this will have a knock affect to the further planned DM test cycles. The SI is currently reviewing the plan and will look at options.
Data non functional testing planning is in progress at the moment. The draft plan has been shared with ESP’s via the SI Technical Data Working Group with our review and assessment leading us to raise concerns that the timelines are very tight and if SIT Non Functional slips this will have an impact on Data Migration Non Functional. A revised walkthrough of the plan is being held today with the plan being discussed at the Ofgem Data Working Group next week the 17th June.
Throughout this update you will note that Xoserve have concerns for the testing phases that are currently being undertaken. We continue to raise these concerns via the appropriate SI and Ofgem Workgroups and governance and have requested that robust entry and exit criteria to be carried out between cycles to ensure readiness for advancement into the next stage and reported to Delivery Group.
Xoserve continue to support the Programme whenever required in order to meet the planned programme milestones.
Please do contact me if you have any questions in relation to this update or within any of the artifacts published on this page via emma.j.lyndon@xoserve.com

CSSC Weekly Programme Status Reports

Switching Programme Weekly Status Report: 3rd July 2020

Switching Programme Weekly Status Report: 3rd July 2020

Last updated on 03 Jul 2020

CSSC Programme Dashboard 2020

Last updated on 16 Jun 2020

Day After Report (DAR) Ofgem Data Working Group 23rd October 2019

Last updated on 28 Oct 2019

DAR for the SI Technical Data Working Group 3rd September 2019

Last updated on 06 Sep 2019

DAR for the Data Working Group 21st August 2019

Last updated on 23 Aug 2019

DAR for Service Management Integration Workshop 13th August 2019

Last updated on 21 Aug 2019

DAR for Ofgem Design Forum 12th August 2019

Last updated on 21 Aug 2019

Network Teleconference - 1st August 2019

Last updated on 09 Aug 2019

Data Working Group - Wednesday 17th July

Last updated on 19 Jul 2019

Switching Programme Delivery Group - Tuesday 16th July

Last updated on 19 Jul 2019

Design Forum - Monday 15th July

Last updated on 19 Jul 2019

Design Forum – Monday 1st July 2019

Last updated on 21 Nov 2019

Implementation Group – Tuesday 2nd July 2019

Last updated on 21 Nov 2019

Ofgem Testing Workgroup – Tuesday 2nd July

Last updated on 21 Nov 2019



CSSC Key Risks Summary

CSSC Key Risks Summary: 7th February 2020

Last updated on 07 Feb 2020



Last Extraordinary DSG Meetings for CSS Consequential Change Meeting - 24th January 2020

View Extraordinary DSG Meetings for CSS Consequential Change Meeting 24th January 2020 documents.



Draft Business Requirements Documents

UK Link File Format Change Summary

Last updated on 09 Sep 2019

Switching Programme Consequential Change - Gemini Business Readiness Document (BRD)

Last updated on 29 Nov 2019

Switching Programme Consequential Change - Gas Transporter (GT) Independent Gas Transporter (IGT) Business Readiness Document (BRD)

Last updated on 29 Nov 2019

Switching Programme Consequential Change - Shipper Business Readiness Document (BRD)

Last updated on 16 Jun 2020

Draft Central Switching Service Consequential (CSSC) Programme Plan on a Page

Last updated on 11 Mar 2019

CSSC End to End To-be Processes

Last updated on 23 Sep 2019

Data Enquiry Service BRD

Last updated on 06 Feb 2020

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