TX SET v2.1 Implementation Plan

Table of Contents A.Shut Down Procedure B.Shut Down Timeline Details C.Conference Calls D.Additional Contingencies

Shut Down Procedure  The shutdown times listed will be strictly adhered to  All MPs should submit transactions well in advance of the shutdown time so that large transaction volumes are not experienced just prior to shutdown –(i.e. if you run batch jobs, schedule them throughout the day)!!!  All MPs shall call-in to each conference call, on-time, during the implementation.  All times listed are Central Prevailing Time

Use of Safety Net  Beginning Thursday, Dec 1 st at 8:00am, the CR will utilize the approved Safety Net process during implementation with a default BGN 02 value to request Move-Ins with requested dates of Dec 1 st through Dec 5 th. If the REP cannot include the actual BGN02, the BGN02 must use the following format (cannot exceed 30 characters): –First 4 spaces= V201 –Next 3 spaces= Abbreviated CR name –Then followed by a unique number for each transaction.  CRs will be required to follow up with the corrected BGN02 on a Safety Net correction to the TDSP once their actual BGN02 is available.  The TDSPs will no longer accept default BGN values on Monday Dec 5 th at 8:00am or as soon as Version 2.1 transactions begin to flow.

814 & 867 Transactions Shut-down timeline  CRs will suspend all 814 transactions (EDI and Portal) to ERCOT on Friday, December 2 nd at 7:00am –In-flight transactions will continue to be processed until the queues have been cleared –What date will the TDSPs use for the due date if 810/867s are held on Friday – not an issue anymore – will process up until 5:00pm on Friday –ERCOT will accept 867s until 5:00pm on Friday. 867s not sent by the TDSP to ERCOT by 5:00pm on Friday may be sent after confirmation from ERCOT on Sunday, December 4 th at the 8:00pm conference call that ERCOT can begin accepting transactions  ERCOT will shutdown all outbound 814 and 867 transactions processing on Friday, Dec 2 nd starting at 6:00pm Friday evening

810 Transactions Shut-down timeline  TDSPs will suspend sending 810 transactions to CRs on Friday Dec 2 nd at 5:00pm  CRs in MOU/EC Service Territory will suspend sending 810s to MOU/EC TDSPs on Friday, Dec 2 nd at 5:00pm  CRs will suspend sending 824s and 997s to TDSPs by Friday Dec 2 nd at 6:00pm

820 Transactions Shut-down timeline  CRs will suspend sending 820_02 transactions to TDSPs on Friday, Dec 2 nd at 5:00pm  CRs that submit 820_02 transactions to their financial institutions and then on to the TDSP should notify their financial institutions of this shut-down.  If 820_03s are being processed, they will adhere to the same shut-down timeline.  TDSPs will respond to CRs with 997s related to 820 Transactions by Friday Dec 2 nd at 6:00pm

650 Transactions Shut-down timeline  CRs will suspend sending 650_01 transactions to TDSPs on Friday, Dec 2 nd at 5:00pm  TDSPs will suspend sending 650_02 transactions to CRs on Friday, Dec 2 nd at 6:00pm  TDSPs will suspend sending 650_04 transactions to CRs on Friday, Dec 2 nd at 5:00pm  CRs will suspend sending 650_05 transactions to TDSPs on Friday, Dec 2 nd at 6:00pm  All 997s will be sent within 1 hour of the deadline for the associated 650 –Note: These timings apply to Reconnects and all other uses of the 650_01 except disconnects for non pay (see slide 10)

 Reconnects will follow the manual spreadsheet format  CRs should contact each TDSP via phone or with any emergency issues  TDSPs will begin their normal reconnect process, contingent upon resources and volumes, on Monday morning, Dec 5 th following conversion. 650 Transactions Shut-down timeline

650 Transactions Shut-down timeline for Disconnect for Non Pay  REPs must stop sending all Disconnect for Non Pay at 8:00am Wednesday, Nov 30 th.  Pending DNPs will continue to be worked according to the DNP procedures  Thanksgiving holiday on November 24 th & 25 th may result in a backlog of DNPs to work the following week  CRs will not be required to resend a 650 for previously sent requests.

814 P-2-P Transactions Shut-down timeline  CRs will suspend sending 814_PC transactions to TDSPs on Friday, Dec 2 nd at 2:00pm  TDSPs will suspend sending 814_PD transactions to CRs on Friday, Dec 2 nd at 6:00pm  All 997s will be sent within 1 hour of the deadline for the associated P-2-P Transaction

Conference Call Times Conference Call Information  password:  Press ‘6’ to mute/un-mute phone Thursday Dec 1 st 4:00pm  ERCOT transaction processing update “in queue” “in process” Overall system health  CRs and TDSPs to provide status (state of systems and processing)

Conference Call Times Friday Dec 2 nd 9:00am  ERCOT transaction processing update “in queue” “in process” Overall system health Friday Dec 2 nd 5:00pm  CRs & TDSPs to confirm 650s, 810s, 820s, 867s, and 814 P-2- Ps have stopped flowing (excluding responses); Confirm all initiating transactions processed.  ERCOT transaction processing update “in queue” “in process” Overall system health

Conference Call Times Saturday Dec 3 rd 6:00 pm  ERCOT declares Go/No-Go, % complete of production verification  CRs and TDSPs provide migration status

Conference Call Times Sunday Dec 4 th 10:00 am  CRs and TDSPs provide migration status Sunday Dec 4 th 2:00 pm  ERCOT provides time at which ERCOT will begin accepting v2.1 transactions  CRs and TDSPs provide migration status  If a Market Participant is not ready will use this time to establish the next conference call

Additional Contingencies  Weather delay –First discussion of weather delay will take place on the Friday 9:00 am conference call. –If delay is not called on Friday 9:00 am, last opportunity for discussion of weather delay will take place on Friday 5:00 pm conference call –If delay is called, there are 2 possible results: Weather does not cause a significant impact on any active MPs. Delay is one week. Weather causes a significant negative impact on one or more active MPs. Delay may be more than one week.  Market Participant or ERCOT Delay –Contingency Plans required due to a Market Participant or ERCOT delay will be developed by affected participants and ERCOT if necessary