Improvements to ‘Failed to Deliver’ CSS Messages
Summary
Since CSS Go-Live a large number of messages have not been successfully delivered due to failures of CSS User's gateways, resulting in CSS exhausting the 12-hour retry period. This Change Proposal has been raised to explore and address this issue
Latest update and next planned activity
Date of latest update
Latest Update
This Change Proposal has been implemented as part of the REC Release on 27 June 2025.
Impacts Overview
Impacted Consumers
Electricity
Gas
Impacted REC Parties and Market Participants
Energy Supplier
DCC
Impacted REC Services
Central Switching Service (CSS)
Priority and rationale
Standard
Priority last updated on 29 May 2026
Solution development
Problem Statement
Following an unexpected or extended period of gateway outage for a CSS User, there is currently no automated process to resend any CSS messages from the CSS Provider that were triggered during the period of outage. This results in the CSS Provider needing to manually correct any issues, which is time consuming and may affect Consumer Switches due to delays in messages being processed.
Proposed solution summary
- As a Consumer, I want the Switching process to work successfully, so that I can switch Energy Supplier without delays or issues.
- As the CSS Provider I want the messages I send to CSS Users to be received and processed successfully, so that there is no interruption to the Switching process or the Consumers’ Switching experience.
- As the CSS User I want to receive CSS messages in a timely manner following any outage of my own gateway or systems, so that there is no interruption to the Switching process or the Consumers’ Switching experience.
No documents available.
Change Plan
Service Provider Impact Assessment close
Completed
Start:
09 Nov 2022Due:
25 Jan 2024Completion:
25 Jan 2024Party Impact Assessment trigger
Completed
Start:
25 Jan 2024Due:
02 Feb 2024Completion:
02 Feb 2024Party Impact Assessment close
Completed
Start:
02 Feb 2024Due:
23 Feb 2024Completion:
23 Feb 2024Preliminary Change Report and Consultation issued
Completed
Start:
23 Feb 2024Due:
10 May 2024Completion:
10 May 2024Consultation close
Completed
Start:
10 May 2024Due:
03 Jun 2024Completion:
03 Jun 2024Responsible Committee Decision
Completed
Start:
24 Jul 2024Due:
31 Jul 2024Completion:
31 Jul 2024Final Change Report Issued
Completed
Start:
03 Jun 2024Due:
24 Jul 2024Completion:
19 Jul 2024Original submission
Change details
Ann Perry - -
9 Nov 2022
Change details
Improvements to ‘Failed to Deliver’ CSS Messages
Since Go-Live a large number of messages have been unsuccessfully delivered due to failures of CSS Users gateways, resulting in CSS exhausting the 12-hour retry period.
At this point the baseline design does not support any capability to automatically resend messages once a gateway connectivity is restored by the CSS User.
The issue is caused when CSS Users take their gateway off-line for longer than 12 hours for maintenance or they experience an unplanned outage.
At this point the baseline design does not support any capability to automatically resend messages once a gateway connectivity is restored by the CSS User.
The issue is caused when CSS Users take their gateway off-line for longer than 12 hours for maintenance or they experience an unplanned outage.
Messages will not be received by the CSS User which will result in data becoming out of sync with CSS.
A significant amount of manual work is required by CSS and the Switching Operator to manage and resolve those issues, which has not been planned for or costed.
A significant amount of manual work is required by CSS and the Switching Operator to manage and resolve those issues, which has not been planned for or costed.
A number of potential solutions should be considered by Industry during the REC Change Process in order to determine the most appropriate solution.
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Impacts
Electricity, Gas
Switching experience
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No details provided
TBC
No details provided
-
No details provided
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No details provided
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No details provided
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Central Switching Service (CSS), Switching Operator
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Energy Suppliers, DCC
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No details provided
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No details provided
Priority & timing
No
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No details provided
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Activity
Proposed solution summary changed to As a Consumer, I want the Switching process to work successfully, so that I can switch Energy Supplier without delays or issues.As the CSS Provider I want the messages I send to CSS Users to be received and proce…
Proposed solution summary changed to As a Consumer, I want the Switching process to work successfully, so that I can switch Energy Supplier without delays or issues.As the CSS Provider I want the messages I send to CSS Users to be received and processed successfully, so that there is no interruption to the Switching process or the Consumers’ Switching experience.As the CSS User I want to receive CSS messages in a timely manner following any outage of my own gateway or systems, so that there is no interruption to the Switching process or the Consumers’ Switching experience..
Show moreImplementation Date has been updated to 27 Jun 2025.
caroline.milner, Orphaned SME: Lead Assurance Analyst have been allocated as SME.