NOTICE DATE: October 15, 2021

NOTICE TYPE: M-B101521-01 Outage - Retail/Wholesale

SHORT DESCRIPTION: Unplanned system maintenance with impacted services - MPIM

INTENDED AUDIENCE: ERCOT Market Participants

DAYS AFFECTED: October 15, 2021 16:00 – 18:00

LONG DESCRIPTION: ERCOT will be performing unplanned system maintenance of MPIM database on October 15, 2021.

During the October 15, 2021 16:00 – 18:00 outage window, Market Participants may experience intermittent issues with the following services:

• Market Participant Identity Manager (MPIM)

Note that the outage start and end times may be delayed depending on the current system conditions.

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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