NOTICE DATE: February 2, 2026

NOTICE TYPE: M-A020226-01 Operations

SHORT DESCRIPTION: Retirement of Pre-Real-Time Co-Optimization (RTC) System Operations Test Environment (SOTE) and Updated Citrix Shortcuts to access RTC+B SOTE

INTENDED AUDIENCE: All Market Participants

DAYS AFFECTED: February 4, 2026

LONG DESCRIPTION: Effective February 4, 2026, the Pre-RTC SOTE system will be retired. Shortcuts on the Citrix Gateway have been updated to provide access to the RTC+B SOTE system.

The new shortcuts will no longer include the word "RTC" in their names.

To assist with this transition, the SOTE Outage Studies document has been updated and attached to this notice. This document includes detailed guidance and helpful information for working with the SOTE system

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 ClientServices@ercot.com.

If you are receiving email from a public ERCOT distribution list that you no longer wish to receive, please follow this link in order to unsubscribe from this list: http://lists.ercot.com.

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