NOTICE DATE: October 5, 2012

NOTICE TYPE: W-A091912-02 Release – Wholesale

SHORT DESCRIPTION: REMINDER – Implementation of market-facing changes for October 2012

INTENDED AUDIENCE: ERCOT Market Participants

DAYS AFFECTED: October 16 – 18, 2012

LONG DESCRIPTION: ERCOT will be implementing a number of market-facing changes in the production environment on October 16 – 18, 2012. Please see the attached spreadsheet for the description and estimate of the release date for each change.

Note that items related to Nodal Protocol Revision Request (NPRR) 365, Change in Resource Outage Approvals from Eight to 45 Days (formerly “Change in Resource Outage Approvals from Eight to 90 Days”) have been removed from this release window. Implementation details for NPRR365 will be provided in a separate Market Notice at a later date.

ADDITIONAL INFORMATION: ERCOT may experience intermittent service interruptions during the implementation period. The systems include, but are not limited to:

· Market Participant notifications

· Outage Scheduler User Interface

· Market Management System User Interface

· Market Participant Identity Management

· Components of the ERCOT Market Information System (MIS) may be intermittently unavailable including:

· Report publishing to the MIS

· Current Day Reports (CDRs) without retry functionality may not be rerun for the missed postings during the outage time

· MIS and ERCOT.com dashboards will be intermittently unavailable

· During this outage, please use the following URLs to directly access the Market Manager and Outage Scheduler:

· https://mis.ercot.com/mmsui/mmsui/displayTradesLanding.action

· https://mis.ercot.com/osrui/osrui/Summary.action

· Components of the External Web Services (EWS) may be intermittently unavailable

Information on upcoming releases can be found on the ERCOT Multi Year Project Priority List (PPL) at http://www.ercot.com/services/projects/.

CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at [log in to unmask].

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