1. 21 September 20111 ROI HSP Design Clarification Truncation of Leading and Trailing Zeros in Decimal Fields

2. 21 September 20112 Data Changes in Market Messages to Support new TIBCO-based Communications Background The introduction of the new TIBCO-based communications technology requires a change in the way decimal fields are handled. Summary of Impact Where a field is defined as decimal within the harmonised schema, then any leading or trailing zeros are not populated. This change is outlined overleaf. This change will be added to the ROI Extended Impact Summary spreadsheet as presented at the ROI MP Planning Workshop on 17 April 2012. The updated presentation will be Version 1.3 and will be replaced in the HSP Project Folder on the RMDS Calendar.

3. 21 September 20113 Truncation of leading and trailing zeros on all decimal fields in outbound to Supplier messages 27.300 To-Be (field value in 341 message) Interval Value (total digits = 9, post-decimal digits = 3) Planning and Implementation Notes –See the attached list of all decimal fields on all Outbound Messages (Source: HBL V2.3) –This change does not impact on the HBL or Harmonised Schema –All affected decimal fields contain a decimal point in the XML message –Validation rules for decimal fields on inbound messages are unchanged –The schema rules for total number of digits and post-decimal digits for all decimal fields are unchanged –This is a feature of the new TIBCO applications and is already working this way in the NI market. ESBN will also adopt this new feature upon Harmonisation go live in the ROI 27.3 As-Is (field value in 341 message) Interval Value (total digits = 9, post-decimal digits = 3) 03.1415 TransformerLossFactor (total digits = 6, post-decimal digits = 4) TrailingLeading 3.1415 TransformerLossFactor (total digits = 6, post-decimal digits = 4)

4. 21 September 20114 ROI HSP Design Clarification File Naming Conventions (fully replaces previous clarification issued to IGG on 27 th June, 2012)

5. 21 September 20115 Mxxxx_YYYYMMDDHHMMSSSSS To-Be Outbound from Supplier (via Webforms) Planning and Implementation Notes –This change does not impact on the HBL or Harmonised Schema –This change is separate from the12 message name changes in the Harmonised Schema (see the category “Message Name Changed” in the ROI Extended Impact Summary spreadsheet on page 16 of the MP Planning Workshop slide deck) –Update 21/8/212: there are no restrictions, other than uniqueness, on the naming of inbound-to-Networks messages by Suppliers As-Is 1. Change in Market Message File Naming convention Inbound to Supplier Mxxxx_YYYYMMDDHHMMSSSSS MM Number Date and Time MM Number DSO_MIM_xxxx_sssssssssssss_pppp In all folders - Pending, Outbound, Inbound and all archive folders. 602 and 601 MMs do not have the DSO_ prefix. Date and Time Seconds since base date TIBCO Process ID ROI Mkt