***** EXTERNAL email. Please be cautious and evaluate before you click on links, open attachments, or provide credentials. ***** NOTICE DATE: September 15, 2017 NOTICE TYPE: R-A081617-03 Release-Retail SHORT DESCRIPTION: Reminder - Retail Release September 2017 INTENDED AUDIENCE: ERCOT Market Participants DAY AFFECTED: September 17, 2017 6:00 AM to September 18, 2017 12:00 AM LONG DESCRIPTION: ERCOT will be performing system maintenance in the production environment on September 17, 2017 06:00 AM to September 18, 2017 12:00 AM. Please note that the maintenance window has been reduced from the time frame that was communicated in earlier Market Notices. ADDITIONAL INFORMATION: ERCOT systems may experience intermittent service interruptions during the implementation period. Areas impacted during the maintenance window include, but are not limited to: * Market Participants utilizing NAESB to send/receive transactions to/from ERCOT will NOT be able to send/receive transactions to/from ERCOT during the outage. This includes all retail transactions. * 867 transactions will NOT be forwarded during the outage. * 997 Functional Acknowledgements will NOT be sent during the outage. * MarkeTrak will be unavailable for the duration of the outage. * Retail Application components of the Market Information System (MIS) and the Retail API will be unavailable * Retail Reports and Extracts may be impacted during the outage timeframe * eService application will be unavailable on the MIS * Find ESIID and Find Transaction will be unavailable 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]<mailto:[log in to unmask]>. If you are receiving email from an 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. sa