The Change Process

This is the process through which parties can propose changes to the Wholesale-Retail Code (WRC) and Market Arrangements Code (MAC). The Panel considers each change and recommends to Ofwat whether it should be implemented into the market codes. To support the Panel and Ofwat, MOSL assesses the change and prepares a report. In doing so it may establish sub-groups or working groups and manage consultations on the instruction of the Panel. We encourage parties that are considering raising a change to contact in advance so that we can support the Proposer develop the change. MOSL is committed to ensuring change proposals are properly and fairly assessed and further information on how it does this and its role in the process is outlined within its Change Charter.

Raising a Change

To raise a Change for the Panel to consider, please contact with your Change Proposal, using the templates provided in the Related Documents section at the bottom of this page.

 When raising a change please be aware of the Change Timetable, which sets out the deadline for when a change proposal needs to be raised in order to be considered at the next Panel meeting.

 For guidance on the Change Process, please view the Change Handbook provided in the Related Documents section at the bottom of this page.

What happens next? Once a change has been raised, the formal process is:

Change Register

The Change Register below contains information on all Change Proposals, past or current.

Publicly available information, such as the original Change Proposal Form, Sub-Group papers, Consultation and Recommendation Reports are available, which provide a life-cycle view of each Change Proposal.

The search fields below allow specific Change Proposals to be searched and the sort bar allows Change Proposals to be ordered by number, name, status or implementation date.

If you have any questions regarding a Change Proposal please contact the change mailbox.


The Change Report

The Change Assessment and Implementation Programme Report details the status and activity of all in flight Change Proposals and provides a forecast of future changes. This report is published each month and can be found here.

Implementation Date

Reference Title Status Implementation Date
CPW001Cross Border Matters Implemented 02 Oct 2017
CPW002CSD0301 Updates - Meter Treatment Implemented 02 Oct 2017
CPW003CSD0301 Updates - Meter Networks Implemented 02 Oct 2017
CPW004CSD0301 Updates - Meter Networks (Future) Implemented 02 Oct 2017
CPW005Self Supply Implemented 03 Jul 2017
CPW006CSD0301 - New data item updates Implemented 02 Oct 2017
CPW007Alignment to Customer Protection Code of Practice Implemented 02 Oct 2017
CPW008Direction to Supply Implemented 02 Oct 2017
CPW009CSD 0302 updates - alignment with CSD 0301 Implemented 02 Oct 2017
CPW010Emergency Contact Details Implemented 28 Sep 2018
CPW011New Read Type D3010 Withdrawn -
CPW012Flags on D1 Disaggregated Settlement Report Rejected -
CPW013Meter Reading Validation Rejected -
CPW014CSD 0301 Updates Implemented 18 May 2018
CPW015CSD 0101 Clarification Implemented 02 Oct 2017
CPW016CSD0104 Clarification – Meter Networks Implemented 02 Oct 2017
CPW017CSD0105 Clarifications and updates Implemented 02 Oct 2017
CPW018Clarification of Unsecured Credit Allowance Implemented 23 Apr 2018
CPW019Alternative Eligible Credit Support Implemented 31 Jul 2018
CPW020Proposal to amend the wording in the F02 Complaint Form Implemented 01 Dec 2017
CPW021Negotiating Alternative Eligible Credit Support reasonably and in good faith Implemented 14 Jul 2017
CPW022New Connection Retailer Unknown Implemented 18 May 2018
CPM001Change Proposal Form Update Implemented 03 Jul 2017
CPM003Revised MIMP Committee Composition Implemented 01 Dec 2017
CPM004Board Nomination Process Extension Implemented 15 Sep 2017
ICP/WRC003Alignment with Exit Regulations Implemented 02 Oct 2017
ICP/WRC036Data Format Updates Implemented 02 Oct 2017
ICP/WRC048Tariff Table Updates Implemented 02 Oct 2017
ICP/WRC051Performance Charge Alignment with ISA Implemented 02 Oct 2017
ICP/WRC053SPID Pairing Updates Implemented 02 Oct 2017
ICP/WRC055Trade Effluent Updates - SVAM Subtract and Calculated Discharge Frequency Implemented 02 Oct 2017
ICP/WRC059Settlement Updates Implemented 02 Oct 2017
CPW025Extending TCORR Functionality for Inactive Data Items Implemented 17 May 2019
CPW024Settlement Renaming and Report Issuing Updates Implemented 01 Dec 2017
CPW023Market Entry and Re-Assurance Updates Implemented 12 Mar 2018
CPW027QC Error Code Implemented 18 May 2018
CPM006Introducing a process for Urgent Change Proposals Implemented 08 Apr 2020
CPW026Removing SPID version design Implemented 28 Sep 2018
CPW028Unpaired SPIDs Implemented 28 Sep 2018
CPW031Extending the new connection suspension period Implemented 03 Mar 2018
CPW029 & CPM007GDPR and Data Protection Provisions Updates Implemented 30 Mar 2018
CPW030Review of Market Performance Standards Implemented 01 Apr 2018
CPW032Amend H/04 to clarify Tariff effective date Implemented 28 Sep 2018
CPM009Further Board Nomination Process Extension Implemented 16 Mar 2018
CPM005Market Entry and Re-Assurance Updates Withdrawn -
CPW033Meter effective to date field in MDS_METER report Implemented 26 Oct 2018
CPM010Amendments to the Retailer Board Nomination Process Implemented 31 Jul 2018
CPW036G/02 Form Amendments and G/03 Temporary Consent Form Implemented 28 Sep 2018
CPM011MOSL invoices and payment terms Implemented 31 Jul 2018
CPW034Housekeeping changes to CSD 0301 Implemented 25 May 2018
CPM008Redistribution of Market Performance Standards Charges Implemented 29 Mar 2019
CPW035F01 Form Amendments Implemented 28 Sep 2018
CPW037Removing the Error Codes list from CSD 0301 Implemented 28 Sep 2018
CPW038Tariffs Report updates Implemented 17 May 2019
CPW039 & DCP002Deferral of Final Settlement Runs Implemented 31 Aug 2018
CPW040Changes to the contents of the NAPS Report Implemented 17 May 2019
CPW041G read removal governance Implemented 29 Mar 2019
CPW042Provision of adding re–read flag into the MDS Meter Reads file Implemented 17 May 2019
CPW043Drafting clarifications for CPW028 Implemented 26 Oct 2018
CPW044Digital Certificates & Public Keys updates Implemented 03 Dec 2018
CPW045Updates to the Service Management Interface Implemented 03 Dec 2018
CPW046Changes to the unplanned settlement process Implemented 03 Dec 2018
CPW047Enabling Sewerage Wholesalers to create meter networks Implemented 26 Jul 2019
CPW048Alternative Payment Terms Implemented 31 Jan 2019
CPW049 & CPM012Operational Performance Standards Review Implemented 01 Apr 2019
CPW050Changes to the Long Unread Meters Report Implemented 26 Jul 2019
CPW051Market Incident Management Plan amendments Implemented 29 Mar 2019
CPW055Wholesale Retail Code inconsistency Implemented 28 Feb 2019
CPW052Improving transparency of Alternative Credit Arrangements Implemented 29 Mar 2019
CPW053MO Transaction Processing and Reporting Implemented 17 May 2019
CPW054Housekeeping Changes to Market Codes Implemented 29 Mar 2019
CPW056Cascade Erasure Implemented 08 Nov 2019
CPM013Adding the Customer Representative as a Voting Panel Member Implemented 20 Sep 2019
CPW057Improving transparency of Credit Guarantee Arrangements Implemented 30 Sep 2019
CPW058Removing Processes A1-A5 (Developer Services) Implemented 26 Jul 2019
CPM014Market Performance Standards Charges Redistribution Payment Clarification Implemented 26 Jul 2019
CPM015 & CPW071Panel self-governance Awaiting Authority Decision -
CPM016Panel Voting Majorities Implemented 23 Aug 2019
CPW062Household Indicator Flag Rejected -
CPW066Estimation Review Implemented 14 Feb 2020
CPW060Clarifying credit scores and ratings for the purposes of Unsecured Credit Allowances Implemented 30 Sep 2019
CPW061Unsecured Credit Allowance reflecting payment history Rejected -
CPW063Chargeable Data - Fixed RTS Withdrawn -
CPW064Changes to Corrective Settlement Runs for Individual Supply Points Implemented 14 Feb 2020
CPW065Retailer Notifications Implemented 15 May 2020
CPW067Bulk Submission of Service Requests via MS Excel Awaiting Authority Decision -
CPW068 & CPM017Market Incident Management Plan Committee Revisions Implemented 28 Aug 2020
CPW059Changes to Review Obligations Implemented 15 Feb 2021
CPW069Right of a Retailer to appoint an Accredited Entity to repair or replace a faulty meter when a Wholesaler misses the associated SLA Rejected -
CPW070Bilaterals Interface Solution Change Proposal 31 Jul 2021
CPW072Setting MPS 15 charges to zero Implemented 01 Nov 2019
CPM018Treatment of Market Performance Standard charges and Operational Performance Standard charges Implemented 01 Jan 2020
CPW073Updates to GDPR Personal Data Warnings in CSD 0301 Implemented 14 Feb 2020
CPW074Introduction of a Retailer SLA in relation submission of trade effluent market forms to Wholesalers. Implemented 28 Aug 2020
CPW075Settlement Estimation - Remove estimated meter readings when forward estimating Rejected -
CPW076Change to the current KPI for CSD002 OPS Measure C1a Withdrawn -
CPW077Establishing Trade Effluent charging strength methodology Implemented 06 Nov 2020
CPW078/CPM020Priority Performance Regime Changes for April 2020 Implemented 01 Apr 2020
CPM019GDPR Data Security Standards Implemented 06 Nov 2020
CPW079Protections for Credit Support Security Implemented 14 Feb 2020
CPW080Simplification of the Default and Termination Process Awaiting Authority Decision -
CPW081Improving transparency of Alternative Payment Terms Implemented 01 Apr 2020
CPW082Gap Site Incentive Scheme Implemented 01 Apr 2020
CPW083Vacancy Incentive Scheme Implemented 15 May 2020
CPW084Introducing a Retailer Measure of Experience (R-MeX). Implemented 01 Apr 2020
CPW085Premises Vacant transaction link to DPID Design -
CPM021Panel Membership and Voting Rights Design -
CPW086Unsecured Credit Allowance – Rebalancing Rejected -
CPW087Ability for Wholesalers to add meter reads Implemented 06 Nov 2020
CPW088Ability for Wholesalers and Retailers to add Meter Location Data, and GIS X/Y Details. Rejected -
CPW089T101 Adding Billing Address fields Awaiting Implementation 14 May 2021
CPM022Urgent Change: Reducing Panel Quorum Implemented 07 Oct 2020
CPM023/CPW090Suspension of Performance Standard Charges Implemented 23 Mar 2020
CPW091Temporary Changes to Vacancy Implemented 30 Mar 2020
CPW093Payment deferral interim measures Implemented 30 Mar 2020
CPM024Urgent housekeeping alignment of CPM020 with CPM023 Implemented 01 Apr 2020
CPW094Temporary Change to Disconnections Implemented 08 Apr 2020
CPW095Urgent: Maintain Credit Requirements Implemented 16 Apr 2020
CPM026Panel Chair and Alternate Implemented 28 Aug 2020
CPW092/CPM029Unified Disputes Process and Committee Implemented 13 Nov 2020
CPW096Urgent: Payment Deferral Medium Term Implemented 01 May 2020
CPM027/CPW098Extending the Suspension of Market and Operational Performance Standard Charges due to Covid 19 Implemented 01 Jun 2020
CPM025/CPW097Suspension of Market Performance Standard Charges following an interim supply event Implemented 01 Jul 2020
CPW099Clarify the responsibilities of Trading Parties during a planned event Awaiting Implementation -
CPW100Urgent: Revision to Credit Support Requirement under CPW095 Rejected -
CPM028Aligning MOSL Board Governance with the Articles of Association Implemented 01 Sep 2020
CPW102/CPM030Gender Neutrality in the Market Codes Implemented 06 Nov 2020
CPW101/CPM031Unwinding Temporary Covid-19 Arrangements in the Business Retail Market Implemented 01 Aug 2020
CPW103/CPM032Interim Supply Process Amendments Implemented 09 Sep 2020
CPM033Improved process for managing Data Subject Rights Requests Awaiting Implementation 14 May 2021
CPM034Retailer Panel Member Changes Implemented 01 Feb 2021
CPM036Provision to vary term of Panel Members Implemented 28 Jan 2021
CPM035Panel Election Streamlining Awaiting Authority Decision 15 Feb 2021
CPW104Housekeeping changes to facilitate the Performance Regime introduced in April 2020 Awaiting Implementation 15 Feb 2021
CPW105Provisions of Information Obligation Awaiting Authority Decision -
CPW106Management of Long-Term Vacant Supply Points Industry Consultation -
CPW107Covid-19 Temporary Vacancy exemptions for Credit Support Implemented 23 Oct 2020
CPW108Agreement to Unplanned Settlement Runs Implemented 26 Jan 2021
CPW110Sharing Non-Household Emergency Contact Details Design -
CPW111Housekeeping change to align the codes with CMOS Awaiting Authority Decision -
CPW112Clarifications to CSD 0102 and CSD 0105 Awaiting Authority Decision 14 May 2021
CPW113Housekeeping Changes to Correct Typographical Errors and Enhance Standardisation Awaiting Implementation 14 May 2021
CPW114/CPM037Housekeeping Changes to Correct Typographical Errors and Enhance Standardisation Awaiting Implementation 14 May 2021
CPW109Changing the Constraints on Customer Reads Awaiting Authority Decision 14 May 2021
CPW115Amending and updating the definition of Insolvency Event to remove the ‘negative net assets’ criterion Rejected -
CPW116/CPM038Clarification and removal of redundant clauses in the Unified Disputes Process. Change Proposal -
CPW117Shortening the late payment default timeline for a credit support reduction Change Proposal -

Change Timetable

The below table highlights the last day in which change proposals can be raised in order to be consideration at the next Panel meeting.

We encourage Trading Parties that are considering on raising a change to contact MOSL at least one month in advance of the specified dates below. MOSL will then work with the Proposer to support and shape the development of the change and to ensure any questions are clarified in advance of the change being considered by the Panel.

Note: A Change Proposal is officially confirmed as raised once the Change Proposal has been given a unique reference number by MOSL and has been published on the MOSL Website.

Panel date Last Day to raise change
30 March 2021 16 March 2021
27 April 2021 13 April 2021
25 May 2021 11 May 2021
29 June 2021 15 June 2021
20 July 2021 06 July 2021
31 August 2021 16 August 2021
28 September2021 14 September2021
26 October 2021 12 October 2021
30 November 2021 16 November 2021
14 December 2021 30 November 2021

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