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Interconnector Registration and Entering the Market

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Interconnector Registration and Entering the Market

Interconnector Administrator and/or an Interconnector Error Administrator Guidance Note.

This is an overview of the end to end process for registering an Interconnector and entering the market as an Interconnector Administrator (IA) and / or an Interconnector Error Administrator (IEA) in the Central Volume Allocation (CVA) Market.

Interconnector Users (IUs) may also find it useful to understand their relationship with the IEA and IA, but for the process of becoming an IU, please refer to the Market Entry diagram on the Elexon website.

If you are considering entering the market as an IA and / or an IEA, Elexon recommends that you contact its Participant Management team (market.entry@elexon.co.uk) to arrange a meeting with them to discuss your intentions and they can provide further support and guidance. Market Entry meetings are free of charge to potential Parties, and can be held either at Elexon’s office or via teleconference.

The high-level processes to register an Interconnector include the:

0.0.1 CVA Market Entry - BSC Party registration of the Interconnector Administrator (IA) and Interconnector Error Administrator (IEA);

0.0.2 Appointment/consent of the Interconnector Administrator (IA), and the Interconnector Error Administrator (IEA) by the National Electricity Transmission System Operator (NETSO) or Distribution System Operator (DSO) (as the case may be, and in their role as the Interconnected System Operator (ISO)) to whose System the Interconnector is connected to;

0.0.3 Registration of the Interconnector Boundary Point by the ISO;

0.0.4 Registration of the Interconnector Metering System, Aggregation Rule, and appointment of the CVA Meter Operator Agent (CVA MOA), by the ISO;

0.0.5 Registration of Interconnector BM Units by the IEA;

0.0.6 Registration of Interconnector BM Units by the NETSO;

0.0.7 Registration of Interconnector BM Units by an Interconnector User (IU).

The normal timescales for completing the Interconnector, and the BM Unit, registration process can vary from between 2 to 4 months1 , depending on if EDL/EDT are required by the NETSO. This timescale also includes the Market Entry process, as both the BSC Party and BM Unit Registration can usually be completed in parallel.

CVA Market Entry

0.1 Overview

It is a requirement for all BSC Parties to complete CVA Market Entry. This section provides an overview of the steps involved and offers advice on how to complete each step.

The normal timescale for completing the Market Entry process is 2 - 4 months, depending on the individual requirements. This timescale also includes the BSC BM Unit Registration process, as both the BSC Party and BSC BM Unit Registration can usually be completed in parallel.

The Participant Management team is happy to have an initial meeting to discuss, understand your requirements and give an overview of the process. To arrange a meeting, please complete the Market Entry Meeting Request Form.

Accession

The Market Entry process is initiated by Accession to the BSC. At this point you will be considered a BSC Party, and will be subject to Elexon’s Base Monthly Charge of £250 (+VAT) per calendar month or part thereof.

When you are ready to Accede to the BSC, you need to submit:

    • A undated Accession Agreement. This is dated and countersigned by our Director on the date of Accession.

    • One-off £500 Accession Fee payable by Cheque/BACS or CHAPS. To obtain the Elexon bank details, please submit your request using the Elexon Support enquiry service.

Once Elexon have the above forms and the Accession Fee, they will arrange an Accession Date of your preference, after which you will begin to be invoiced the Elexon Base Monthly Charge.

BSCP38 - Authorised Signatories

Authorised Signatories are the people appointed to carry out activities under the BSC. Your Authorised Signatory will also need to sign off documentation and forms relating to the Market Entry process. To appoint your first set of Authorised Signatories Elexon requires either:

    • BSCP38/5.1 with the first signatories details in both part A and C of the form. Additional signatories only need to complete part C; and

    • A Director’s letter on company headed letter paper nominating the first Category A signatory. The Market Entry team can provide a template for this.

Or

    • A Director’s letter on company headed letter paper nominating the first Category A signatory. The Market Entry team can provide a template for this.

0.1 Communication Lines

BSC Parties are required to acquire a communications method for Elexon’s systems to communicate with their own. There are two options for this:

    • the Low Grade Service. This is a download from the public internet, takes five Working Days to set up and is free to BSC Parties; and

    • the High Grade Service. This involves the installation of a direct connection to your office, through which data will be pushed in real time. There are costs associated with the High Grade Service.

IEAs will not need to communicate with Central Systems by default, but may choose to receive Settlement data if they wish.

BSCP70 - CVA Qualification Testing

BSC Parties are required to complete CVA Qualification to certify that the Party’s CVA system can correctly interact with Elexon’s systems and validate the format of any data that they receive. Parties are required to build or procure their own system, which is qualified on an individual basis. The principle of CVA Qualification is described in BSCP70 and the CVA Qualification New Participants Guide. To complete CVA Qualification, there are three routes:

    • Full testing of all relevant flows. The testing is free to entering Parties and can be repeated multiple times if the first test is not successful. The testing takes approximately half a day and can be booked using the BSCP70/01(a) booking form2 ;

    • Waiver testing against an already Qualified Parties system. If you have agreed with a Party that has already Qualified in the role to make use of their system, then you can waiver the testing. To do so complete the BSCP70/02 waiver application listing the flows which you wish to waiver. This should be accompanied by supporting evidence in the form of a letter from the supporting Party;

Opt out of testing. This is not a method that Elexon recommends as it provides no assurance to the Party that they are able to correctly receive any data that they receive. To opt out, submit the BSCP70/01(a) form and acknowledge in the email that not testing is done so at the Parties own risk.

The exact flows you will be required to test will depend upon your set up and if you wish to receive Settlement data. It is the responsibility of participants to assess which data flows they will need to test, but the likely flows are listed below:

Flow

Participant

Name

Purpose

CRA-I014

• IEA

• IA

Registration Report

To enable Party to ensure that its registration details are accurately recorded in Central Systems. This includes Party Id, Name, address etc

ECVAA-I007

• IEA

ECVNAA Feedback

To confirm to Party that an Authorisation has been processed

ECVAA-I008

• IEA

MVRNAA Feedback

To confirm to Party that an MVRNA Authorisation has been received

ECVAA-I009

• IEA

ECVN Feedback

To report the rejection (for business reasons) of a received ECVN

ECVAA-I010

• IEA

MVRN Feedback

To report the rejection (for business reasons) of a received MRVN

ECVAA-I013

• IEA

Authorisation Report

To enable Party to check the authorisations it has in place.

ECVAA-I014

• IEA

Notification Report

To enable Party to check its Notifications received by Central Systems

ECVAA-I022

• IEA

Forward Contract Report

To enable Party to check its contract position for the following 7 Settlement Days

ECVAA-I028

• IEA

ECVN Acceptance Feedback

To confirm to Party that Notification has passed validation and been accepted by the system

ECVAA-I029

• IEA

MVRN Acceptance Feedback

To confirm to Party that Notification has passed validation and been accepted by the system

SAA-I006

• IA

BM Unit Metered Volumes for Interconnector Users

To confirm Deemed Metered Volumes

SAA-I014*

• IEA

Settlement Reports

To enable a Party to check its Settlement position

SAA-I017

• IA

SAA Data Exception Report

To inform the Interconnector Administrator that SAA-I006 has failed validation

CDCA-I041

• IA

Interconnector Aggregation Report

To report back the Metered Volumes to the Interconnector Administrator

*Please note the tests as part of CVA Qualification will use Standard Data.

If you are building your own CVA Software, please refer to the following documents:

If you have further questions on building CVA software please contact BSCServiceDesk@cgi.com, 0370 010 6950, where you will be directed to the technical contacts for CVA testing.

BSCP301/04a - Funds Accession form

All BSC Parties are required to register with the Funds Accession Agent (FAA) at least 10WD prior to registering in Central Systems. This can be completed online via the Elexon Kinnect Customer Solution or using the BSCP301/04(a) form. Please note that the FAA requires you to have a UK bank account, that is an account with a bank that has a branch based in the UK and used GBP is its principal currency.

Credit Cover, and Contacts

There is more information on Credit Cover and Credit Default on the Guidance section of the BSC Website (under Credit and under Party Default) as a consideration prior to Trading. There is also a training video on Credit Cover and Credit default on the training section of the BSC Website. Credit Cover is required for the IEA role only.

Parties are required to provide two credit contacts to register in BSC Central Systems who can be contacted in and out of office hours, this can be added online via the Elexon Kinnect Customer Solution.

Nominate operational contacts

Elexon requires Parties to nominate contacts for who should be contacted in relation to different operational processes under the BSC. The nominated persons should be authorised to undertake activities relating to the area for which they have been nominated. Operational contacts can be added online via the Elexon Kinnect Customer Solution or can be declared using the contacts spreadsheet, the template for which can be provided by the Market Entry team.

BSCP65/01 – Register Party Role

When you have completed CVA Qualification, you will need to complete a BSCP65/01 Form in order to register in our Central Systems in the role of IA and IEA. Alternatively, this information can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution)

If completing the BSCP65/91 form, the IA and / or IEA boxes in the Participation Capacity Details box need to be ticked, along with a required Effective From Date. Where registering as the IEA, the Interconnector ID (e.g. FRANCE) needs to be provided in the last box on the BSCP65/01 Form, and match the ID as agreed on the “Interconnector Administrator/Error Administrator Appointment – Part A Notification of the Appointment” Form completed by the Interconnected System Operator (ISO).

Appointment of the IA/IEA by the ISO

This process can be completed in conjunction with the Market Entry process. As per Section K 5.4.3 of the BSC, the ISO must appoint a Party3 as the IA and the IEA in relation to the Interconnector, and the Party(s) must consent to this appointment. We will send an IA/IEA Appointment form to the National Grid Electricity System Operator (NGESO) and request that they complete this form. Once this Appointment Form is received from NGESO, we will forward this form to the Party, requesting that they formally consent to the IA/IEA Appointment:

0.0.1 The ISO must complete an “Interconnector Administrator/Error Administrator Appointment – Part A Notification of the Appointment” Form. Alternatively, this information can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution); and

0.0.2 The Party consenting to this appointment, must complete an “Interconnector Administrator/Error Administrator Appointment – Part B Consent to the Appointment” Form.

A unique Interconnector ID (such as FRANCE, BRITNED, MOYLE etc.) that can uniquely identify the Interconnector will need to be agreed by the ISO and IA/IEA, and stated on these Forms. These forms will be provided to the ISO by the Elexon Market Entry team during the registration process.

As part of the Interconnector registration, there needs to be an agreement with NGESO of which letter to use in the mid-part of the three letter identifier of the Interconnector BM Unit Id - this is to identify the Interconnector in both the NGESO BM Unit Id, and the Settlement BM Unit Id, e.g.

    • FRANCE (IFA) = F (example I_IFD-ACCE1, IFG-ACCE1),

    • BRITNED = B (example I_IBD-ACCE1),

    • MOYLE = M (example I_IMD-ACCE1),

    • EWIC = I (example I_IID-ACCE1).

0.0.3 The letter E should NOT be used, as this has partly been used for the Error Account BMUs (example I_IED-FRAN1).

Registration of the Interconnector Boundary Point

As per Section K 1.4.1 of the BSC, the ISO has to register the Interconnector Transmission System Boundary Point(s) (TSPBs) in accordance with BSCP25.

The ISO is required to submit a BSCP25/5.1 “Registration/De-registration of a Transmission System Boundary Point” Form to register the Interconnector Boundary Point(s), with the TSPB Type of “Interconnector” ticked, along with supporting network diagrams. Alternatively, this information can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution).

Registration of the Interconnector Metering System, Aggregation Rule, and Appointment of CVA Meter Operator Agent (CVA MOA), by the ISO

As per Section K 5.3.1 of the BSC, the ISO is required to install, maintain and operate (or procure the same) the CVA Metering Equipment, to be the Registrant of the Interconnector Metering System, and to appoint a CVA MOA. The ISO also is required to register the Metering System using BSCP20/4.1 “Registration of Metering System” Form.

    • BSCP20/4.1– By 20 WDs prior to the Effective From Date (EFD) to bm.unit@elexon.co.uk and neta@imserv.com. This form details the CVA Metering System Identifier (MSID) being registered for the Interconnector, and the CVA MOA appointed by the ISO4 . The ISO can reserve a CVA MSID for the site in advance by emailing the Central Registration Agent (CRA), stating the Name, whether it is Transmission or Distribution connected, and its location (England and Wales, North of Scotland, or South of Scotland). The CRA will provide details of the CVA MSID.

The CVA MOA appointed by the ISO is required to submit the Meter Technical Details using BSCP20/4.3 “Registration of Meter Technical Details” Form.

    • Metering Equipment should be compliant with the relevant Code of Practice at the time of first registration for Settlement purposes, however should any aspect of your Metering System be unavoidably non-compliant, there is a process for making an application for a Metering Dispensation from the relevant Code Of Practice via BSCP32. Elexon can advise prior to submission and we recommend that the signed BSCP32/4.1 Form and any supporting documentation is submitted at least 14 weeks prior to the EFD. Metering Dispensations should be sent to dispensations@elexon.co.uk. Note that Panel Committees may approve, reject or defer a decision on a Metering Dispensation so the ideal situation is for all metering to be compliant with the relevant Code of Practice. Further information on the Metering Dispensation process can be found on the Metering Dispensations page of the BSC Website.

The NETSO, as the ISO (as per Section R 3.2.2 of the BSC), or the DSO (as per Section R 3.2.3 c) of the BSC), is required to register the Aggregation Rule for the Interconnector using BSCP75/4.2 “Registration of Meter Aggregation Rules for Volume Allocation Units” Form.

    • BSCP75/4.2 - By 20 WDs prior to the EFD to bm.unit@elexon.co.uk and neta@imserv.com. This form details the Aggregation Rules for the Interconnector. For a distribution connected Interconnector, the rule will also need to include reference to a Line Loss Factor (LLF) BSC Section R 3.3.2. Guidance on writing Aggregation Rules can be found in the Aggregation Rules Guidance Note. Note that the identifiers in the Aggregation Rules need to match those in the Meter Technical Details.

    • The ISO will also need to provide site diagram(s) showing the location of the Metering Equipment (in particular the Settlement current and voltage transformers (CTs/VTs)), CT/VT Ratios and any System Connection Points at or near the proposed Boundary Point(s).

    • For a distribution connected Interconnector , the ISO will also need to contact the relevant Licensed Distribution System Operator (LDSO) to request that they send CVA LLFs to Elexon.

    • For a distribution connected Interconnector, the relevant LDSO will need to update the relevant GSP Group Take Aggregation Rules These are prepared by the Central Data Collection Agent (CDCA) and signed off by the LDSO.

Registration of Interconnector, IA & IEA in BSC Central Systems

As per Section K 5.4.1 of the BSC, no Party may Export or Import at an Interconnector Boundary Point unless there is an IEA appointed and registered in the CRA systems in relation to the Interconnector, and as per Section K 5.4.2 of the BSC, the ISO shall not energise a new Interconnector until an IA and an IEA is appointed and registered in the BSC Central systems.

The ISO therefore shall not energise a new Interconnector until the Interconnector metering has been proven, the IA/IEA roles have been registered in the Central Registration Agent (CRA) systems, all other registrations processes have been completed satisfactorily, and Elexon have issued an Approval to Energise the Interconnector.

When all the above steps have been completed and checked by Elexon, Elexon will issue to the ISO an Approval to Energise the Interconnector. This will be for the date requested by the ISO on the various BSCP Forms, or a later date if that is not achievable.

All registration requirements should be completed in time to allow the approval to energise email to be issued at least 4WDs before your required Effective From Date.

The Effective From Date given in the Approval to Energise email is the “BSC Central Systems Go-Live Date” and is the earliest date that the ISO can physically energise its connection to the Transmission / Distribution System, and this is the date that the CDCA will begin to collect Metered Data for the Interconnector. It does not matter if the physical energisation date of the Interconnector is after the Effective From Date quoted in the Approval to Energise email, but it must not be before.

Registration of Interconnector BM Units by the IEA

As per Section K 5.5.2 and 5.5.5 of the BSC, the IEA shall, upon its appointment as such becoming effective, shall automatically be allocated (and registered in respect of) two Interconnector BM Units, designated as a Production BM Unit and a Consumption BM Unit respectively, and commonly known as the IEA “Error” BM Units.

The IEA registers the pair of IEA “Error” BM Units for the Interconnector by completing a BSCP15/4.1 “Registration of a BM Unit for a CVA Metering System” Form. Alternatively, this information can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution).

    • BSCP15/4.15 - By 30 WDs prior to the EFD to bm.unit@elexon.co.uk and neta@imserv.com. This form details the BM Units being registered. Further details of registering BM Units can be found in the Balancing Mechanism Units Guidance Note. The new Interconnector Id (e.g. FRANCE, BRITNED) is also required on the BSCP15/4.1 Form. Alternatively, this information can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution).

These BM Units cannot be registered until the IA/IEA roles have been registered in the CRA systems, all other registrations processes have been completed satisfactorily, and Elexon have issued an Approval to Energise to register the Interconnector.

Registration of Interconnector BM Units by the NETSO

As per Section R 7.5 of the BSC, the NETSO shall automatically be allocated (and registered in respect of) two notional BM Units for the Interconnector, designated as a Production BM Unit and a Consumption BM Unit respectively, and which are used for the purpose of allocating and accounting for energy comprised in any system-to-system flows. “System-to-system flows” are those that “arise for the purpose of securing stability of operation on the Total System or an External System”. The NETSO determines (on a basis approved by the Authority) the amounts of energy resulting from system-to-system flows and notifies the IA of the net amount of any flows that arise. The IA then calculates the BM Unit Metered Volumes for NETSO’s Interconnector BM Units based on the values notified, and submits them to the SAA.

To satisfy this, the NETSO registers the pair of “notional” BM Units for the Interconnector by completing a BSCP15/4.1 “Registration of a BM Unit for a CVA Metering System” Form– by 30 WDs prior to the EFD sending to bm.unit@elexon.co.uk and neta@imserv.com. This form details the BM Units being registered. Further details of registering BM Units can be found in the Balancing Mechanism Units Guidance Note. The new Interconnector Id (e.g. FRANCE, BRITNED) is also required on the BSCP15/4.1 Form. Alternatively, this information can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution).

These BM Units cannot be registered until the IA/IEA roles have been registered in the CRA systems, all other registrations processes have been completed satisfactorily, and Elexon have issued an Approval to Energise email to register the Interconnector.

Submission by the IA of SAA-I006 “BM Unit Metered Volumes for Interconnector Users” flow

Once the Interconnector has gone live in the BSC Central Systems, then the IA is required under BSCP04 to submit an SAA-I006 flow to the Settlement Administration Agent (SAA) for each Settlement Day from the “BSC Central Systems Go-Live Date”. This flow contains the Expected Transfer for each Interconnector BM Unit for each IU for each Interconnector ID.

Registration of Interconnector BM Units by an Interconnector User (IU)

For the purposes of the BSC, an Interconnector BM Unit is a notional BM Unit associated with an Interconnector. Interconnector BM Units allow IUs to trade over a particular Interconnector, and always come in pairs. One of the BM Units is for electricity entering the GB Total System over the Interconnector (Production), and the other is for electricity being taken off the GB Total System (Consumption), and commonly known as an Interconnector generation BM Unit (being import to the GB Total System), and an Interconnector demand BM Unit (being export from the GB Total System). Each Interconnector has many pairs of these BM Units, one pair for each IU who has registered to use it.

Please note that a BSC Party must have qualified as an IU (as a Trader Interconnector “TI” Role in the CRA systems) before they can register Interconnector BM Units. For registration as an IU, you should refer to the Market Entry Diagram or the BM Units – Registration of Balancing Mechanism (BM) Units Guidance Note on the Elexon website.

Further information on Interconnector Trading can be found in the Interconnector Trading Guidance Note.

Other Considerations

0.1 Ofgem

In order to participate in the operation of an electricity Interconnector, you must obtain a licence from Ofgem. Further information can be found on the Ofgem Website or by contacting Ofgem (licensing@ofgem.gov.uk) to discuss further.

0.2 CUSC

All users of the Transmission System must accede to the Connection and Use of System Code (CUSC). Further information about CUSC may be found on the NGESO website at https://www.nationalgrideso.com/codes, under Section 9 – Transmission Interconnector, or Section 3 – Distribution Interconnector.

0.3 Trading Units

By default, all Interconnector BM Units are classified as sole Trading Units.

0.4 Definitions

"Interconnector": means Apparatus, connected to a System, for the transfer of electricity to or from the Total System from or to an External System;

"Interconnected System Operator": means, in relation to an Interconnector, the NETSO or Distribution System Operator (as the case may be) to whose System such Interconnector is connected;

"Interconnection Agreement": means an agreement between the Interconnected System Operator and an Externally Interconnected System Operator and/or an Interconnector User relating to an Interconnector and/or an agreement under which an Interconnector User can use an Interconnector;

"Interconnector Administrator": means, in relation to an Interconnector, the Party for the time being which is appointed and has agreed to act as interconnector administrator in accordance with the provisions of Section K;

"Interconnector Error Administrator": means, in relation to an Interconnector, the Party for the time being which is appointed and agrees to act as (or the Party which is otherwise required to act as) interconnector error administrator in accordance with the provisions of Section K;

"Interconnector BM Unit": has the meaning given to that term in Section K5.5.1;

"Interconnector Boundary Point": means a Boundary Point at which an Interconnector is connected to a System;

"Interconnector User": means, in relation to an Interconnector, a Lead Party in respect of an Interconnector BM Unit other than the Interconnector Error Administrator;

"Distribution Interconnector Boundary Point": means a Boundary Point at which a Distribution Interconnector is connected to a Distribution System;

"External Interconnection": has the meaning given to that term in the Grid Code;

"External System": means an electricity transmission system or electricity distribution system which is outside the area specified in Schedule 1 of the Transmission Licence and is electrically linked to a System; except that during the Transition Period: means an electricity transmission system or electricity distribution system which is outside the area covered by the Total System and is electrically linked to a System;

"Externally Interconnected System Operator": means the person which operates an External System;

"Interconnector Metered Volume": means, in relation to an Interconnector, the Metered Volume in respect of a Settlement Period;

Need more information?

Query

Email

Market Entry Process including booking a Market Entry Meeting

market.entry@elexon.co.uk

Registration of BM Units, Registration of Metering, Aggregation Rules, Exempt Export

bm.unit@elexon.co.uk

Line Loss Factors

llfs@elexon.co.uk

Metering Dispensations

dispensations@elexon.co.uk

Trading Units

trading.unit@elexon.co.uk

Electricity Market Reform

contact@emrsettlement.co.uk.

Generation Licenses / Exemptions

licensing@ofgem.gov.uk

CRA / CDCA

neta@imserv.com.

National Grid ESO BM Unit Registration

bmu.registration@nationalgrideso.com

For further information please contact the BSC Service Desk at bscservicedesk@cgi.com or call 0370 010 6950.

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The copyright and other intellectual property rights in this document are vested in Elexon or appear with the consent of the copyright owner. These materials are made available for you for the purposes of your participation in the electricity industry. If you have an interest in the electricity industry, you may view, download, copy, distribute, modify, transmit, publish, sell or create derivative works (in whatever format) from this document or in other cases use for personal academic or other non-commercial purposes. All copyright and other proprietary notices contained in the document must be retained on any copy you make.

All other rights of the copyright owner not expressly dealt with above are reserved.

No representation, warranty or guarantee is made that the information in this document is accurate or complete. While care is taken in the collection and provision of this information, Elexon Limited shall not be liable for any errors, omissions, misstatements or mistakes in any information or damages resulting from the use of this information or action taken in reliance on it.

1 Note that you will also need to register your Interconnector BM Unit with the NETSO, and if new Electronic Data Transfer (EDT) and Electronic Dispatch Logging (EDL) are required, this may require significantly longer timescales. This may in turn impact your Effective From Date under the BSC. Please contact bmu.registration@nationalgrideso.com for further information and timescales

2 Elexon will also need confirmation of the Interconnector Administrator ID, Interconnector Error Administrator ID and Interconnector ID to setup the testing in advance.

3 The ISO can appoint a different Party to be the IA and the IEA

4 This form appoints the MOA, however the MOA may object to the appointment if they don’t believe that they are the MOA for the Metering System.

5 Note that you will also need to register your Interconnector BM Unit with the NETSO, and if new Electronic Data Transfer (EDT) and Electronic Dispatch Logging (EDL) are required, this may require significantly longer timescales. This may in turn impact your Effective From Date under the BSC. Please contact bmu.registration@nationalgrideso.com for further information and timescales.