{"2":{"_":{"2":{"6":{"4":{"3":{"2":{"7":{"_":"START BY: brief, budget and priorities agreed, the backcast start for keys on Fri 17 Dec 2027. That start is a coin flip; for 80% confidence start by Thu 3 Dec 2026, for 90% by Tue 1 Dec 2026."}}},"_":"By the end of this season: Brief agreed; architect and engineer appointed; survey and trial pits done; concept design under way."}},"7":{"1":{"1":{"3":{"1":{"_":"By the end of Fri 15 Jan: Concept chosen."},"_":"By the end of this week-band: Concept chosen."},"_":"By the end of this month: Concept chosen."},"_":"By the end of this season: Concept chosen."},"2":{"1":{"3":{"5":{"_":"By the end of Mon 19 Apr: Building regulations approved."},"6":{"_":"By the end of Tue 20 Apr: Planning permission granted."},"7":{"_":"By the end of Wed 21 Apr: Builder appointed, contract signed."},"_":"By the end of this week-band: Building regulations approved; Planning permission granted; Builder appointed, contract signed."},"_":"By the end of this month: Building regulations approved; Planning permission granted; Builder appointed, contract signed."},"2":{"4":{"7":{"_":"By the end of Fri 28 May: Pre-commencement conditions discharged."},"_":"By the end of this week-band: Pre-commencement conditions discharged."},"_":"By the end of this month: Pre-commencement conditions discharged."},"3":{"1":{"2":{"_":"By the end of Wed 2 Jun: On site."},"_":"By the end of this week-band: On site."},"3":{"3":{"_":"By the end of Thu 17 Jun: Foundations in."},"_":"By the end of this week-band: Foundations in."},"_":"By the end of this month: On site; Foundations in."},"_":"By the end of this season: Building regulations approved; Planning permission granted; Builder appointed, contract signed; Pre-commencement conditions discharged; On site; Foundations in."},"3":{"1":{"1":{"1":{"_":"By the end of Thu 1 Jul: Ground floor deck complete."},"_":"By the end of this week-band: Ground floor deck complete."},"_":"By the end of this month: Ground floor deck complete."},"3":{"2":{"2":{"_":"By the end of Thu 9 Sep: Weathertight: roof on, windows and doors in."},"_":"By the end of this week-band: Weathertight: roof on, windows and doors in."},"5":{"1":{"_":"By the end of Wed 29 Sep: Permanent power on."},"2":{"_":"By the end of Thu 30 Sep: First fix complete, ready for plaster."},"_":"By the end of this week-band: Permanent power on; First fix complete, ready for plaster."},"_":"By the end of this month: Weathertight: roof on, windows and doors in; Permanent power on; First fix complete, ready for plaster."},"_":"By the end of this season: Ground floor deck complete; Weathertight: roof on, windows and doors in; Permanent power on; First fix complete, ready for plaster."},"4":{"1":{"1":{"5":{"_":"By the end of Tue 5 Oct: External works complete."},"_":"By the end of this week-band: External works complete."},"2":{"6":{"_":"By the end of Wed 13 Oct: Plastering complete."},"_":"By the end of this week-band: Plastering complete."},"_":"By the end of this month: External works complete; Plastering complete."},"2":{"2":{"1":{"_":"By the end of Mon 8 Nov: Second fix complete; Decoration and flooring complete."},"_":"By the end of this week-band: Second fix complete; Decoration and flooring complete."},"4":{"2":{"_":"By the end of Tue 23 Nov: Keys handed over."},"_":"By the end of this week-band: Keys handed over."},"_":"By the end of this month: Second fix complete; Decoration and flooring complete; Keys handed over."},"_":"By the end of this season: External works complete; Plastering complete; Second fix complete; Decoration and flooring complete; Keys handed over."},"_":"REFERENCE — keys handed over by Fri 17 Dec 2027: a four-bedroom detached house in the West Midlands, complete, certified and warranted. Backcast: 234.5 working days of levelled work and a 17.6-day project buffer put the start at Mon 14 Dec 2026."}}}},"_":{"_":{"_":{"_":{"_":{"_":{"_":{"_":{"_":{"_":"SPINE — house-2027, on the canonical clock at floor 10 (the address is the date). A test of the backcast form in FIXED mode: every horizon is pre-voiced from a levelled plan, down to the day, where function:backcast would voice only the reference and the live path. Each entry is a STATE: what must be true by the end of that period. The work toward it lives in the ten mirrors, house-2027:<handle>."}}}}}}}}}}