SEC version 125.0 came into effect today, 04 December 2025, to implement the ad hoc SEC Release of MP308 ‘Out-of-Region Communications Hubs’.
The modification was recommended for approval by an ad hoc Change Board on 28 November 2025. Ofgem approved the modification on 03 December 2025.
The following sections were affected by the ad hoc SEC Release:
- SEC Section A ‘ Definitions and Interpretation’
- SEC Section F ‘Smart Metering System Requirements’
- SEC Section K ‘Charging Methodology’
The following SEC Parties are impacted by the ad hoc SEC Release:
- Large Suppliers
- Small Suppliers
- DCC
- Electricity Network Parties
- Gas Network Parties
Where can I access the legal text for the ad hoc SEC Release?
Full marked-up versions of all impacted documents can be downloaded here.
You can download clean versions of the individual SEC documents from the SEC and Supporting Documents section of our website or via CodeWorks.
If you do not have access to Codeworks, please use the following link: Getting access to CodeWorks
Our SEC Document Log lists the versions of each SEC document now in effect following this release.
Where can I find further information about the ad hoc SEC Release?
If you have any questions, you can call the SECAS Helpdesk at 0120 200 6600 or email SEC.Change@talan.com.