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Following a full service review, launched at the Commercial Balancing Services Group, the BM Start-Up generic terms have been changed to reflect greater transparency, resulting in SONAR publishing additional information, including the BMU ids.

Together with the publication of BM Start Up instructions we are also publishing Advance Synchronisation instructions, to distinguish whether the instruction is BM Start Up or Advance Synchronisation, the details will include BPA information for BM Start Up and these fields will be blank if the instruction is an Advance Synchronisation (as cost is not incurred).

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Agree Time / Instruction Time Category Start Time / Earliest Sync Time End Time / Cancel Time Updated
Details 12/05/2026 15:00 Additional GT 12/05/2026 22:00 13/05/2026 22:00 12/05/2026 00:00:00 12/05/2026 15:00:00 HUMR-1 12/05/2026 00:00:00 22:00 13/05/2026 00:00:00 22:00 400 89
Details 12/05/2026 21:22 Additional GT 12/05/2026 21:20 14/05/2026 23:59 12/05/2026 00:00:00 12/05/2026 21:22:00 SUTB-1 12/05/2026 00:00:00 21:20 14/05/2026 00:00:00 23:59 432 45
Details 13/05/2026 12:16 Additional GT 13/05/2026 22:00 14/05/2026 22:00 13/05/2026 00:00:00 13/05/2026 12:16:00 HUMR-1 13/05/2026 00:00:00 22:00 14/05/2026 00:00:00 22:00 400 89
Details 14/05/2026 23:50 Additional GT 14/05/2026 23:50 15/05/2026 23:59 14/05/2026 00:00:00 14/05/2026 23:50:00 SUTB-1 14/05/2026 00:00:00 23:50 15/05/2026 00:00:00 23:59 430 45
Details 14/05/2026 11:28 Additional GT 13/05/2026 22:00 14/05/2026 22:00 14/05/2026 00:00:00 14/05/2026 11:28:00 HUMR-1 13/05/2026 00:00:00 22:00 14/05/2026 00:00:00 22:00 400 89
Details 14/05/2026 23:10 Additional GT 14/05/2026 23:10 16/05/2026 23:59 14/05/2026 00:00:00 14/05/2026 23:10:00 SUTB-1 14/05/2026 00:00:00 23:10 16/05/2026 00:00:00 23:59 430 45
Details 15/05/2026 12:41 Additional GT 15/05/2026 22:00 16/05/2026 22:00 15/05/2026 00:00:00 15/05/2026 12:41:00 HUMR-1 15/05/2026 00:00:00 22:00 16/05/2026 00:00:00 22:00 400 89
Details 15/05/2026 22:46 Additional GT 15/05/2026 22:46 17/05/2026 23:59 15/05/2026 00:00:00 15/05/2026 22:46:00 STUB-1 15/05/2026 00:00:00 22:46 17/05/2026 00:00:00 23:59 502 45
Details 16/05/2026 11:15 Additional GT 16/05/2026 22:00 17/05/2026 22:00 16/05/2026 00:00:00 16/05/2026 11:15:00 HUMR-1 16/05/2026 00:00:00 22:00 17/05/2026 00:00:00 22:00 400 89
Details 17/05/2026 00:02 Additional GT 17/05/2026 00:00 18/05/2026 23:59 17/05/2026 00:00:00 17/05/2026 00:02:00 SUTB-1 17/05/2026 00:00:00 00:00 18/05/2026 00:00:00 23:59 432 45
Details 17/05/2026 14:19 Active Power Reduction below Submitted SEL 18/05/2026 00:00 18/05/2026 23:59 17/05/2026 00:00:00 17/05/2026 14:19:00 PEHE-1 18/05/2026 00:00:00 00:00 18/05/2026 00:00:00 23:59 253 30
Details 17/05/2026 14:19 Active Power Reduction below Submitted SEL 18/05/2026 00:00 18/05/2026 23:59 17/05/2026 00:00:00 17/05/2026 14:19:00 PEHE-1 18/05/2026 00:00:00 00:00 18/05/2026 00:00:00 23:59 507 30
Details 17/05/2026 18:19 Additional GT 17/05/2026 22:00 18/05/2026 22:00 17/05/2026 00:00:00 17/05/2026 18:19:00 HUMR-1 17/05/2026 00:00:00 22:00 18/05/2026 00:00:00 22:00 400 89
Details 17/05/2026 23:15 Additional GT 17/05/2026 23:15 19/05/2026 23:59 17/05/2026 00:00:00 17/05/2026 23:15:00 SUTB-1 17/05/2026 00:00:00 23:15 19/05/2026 00:00:00 23:59 432 45
Details 18/05/2026 16:33 Additional GT 18/05/2026 22:00 19/05/2026 22:00 18/05/2026 00:00:00 18/05/2026 16:33:00 HUMR-1 18/05/2026 00:00:00 22:00 19/05/2026 00:00:00 22:00 400 89
Details 19/05/2026 23:48 Additional GT 18/05/2026 23:50 20/05/2026 23:59 19/05/2026 00:00:00 19/05/2026 23:48:00 SUTB-1 18/05/2026 00:00:00 23:50 20/05/2026 00:00:00 23:59 432 45