{
  "step": "C274",
  "date": "2026-09-24",
  "authorization": "Dean: Proceed following the C273 single-premise omission proposal",
  "question": "Which translations, inherited endpoint radii and specified symmetries remain determined when exactly one of the three placement equations is removed?",
  "variables": [
    "m: MT ON Flood translation",
    "l: LXX OFF Flood translation",
    "s: SP OFF cumulative Flood translation"
  ],
  "fixed_controls": {
    "source_Flood_center_bounds": {
      "MT_ON": [
        -5296,
        -5289
      ],
      "LXX_OFF": [
        -5290,
        -5283
      ],
      "SP_OFF": [
        -4716,
        -4709
      ]
    },
    "Shem_source_offset": -600,
    "Shem_translation_increment": 598,
    "global_Mirror": "M(x)=-x",
    "local_display": "eta=1000(x-1)",
    "phase_components": "center +/- 1/4; chronological order reverses under reflection",
    "retained_source_translation_T": 8993,
    "K": 529
  },
  "premises": [
    {
      "id": "A",
      "name": "MT closing join",
      "row": [
        2,
        0,
        0
      ],
      "rhs": 10580,
      "equation": "m-5289=5889-(m+598)"
    },
    {
      "id": "B",
      "name": "Common MT/LXX Flood shift",
      "row": [
        -1,
        1,
        0
      ],
      "rhs": 0,
      "equation": "l=m"
    },
    {
      "id": "C",
      "name": "SP/MT global Flood-interval reflection",
      "row": [
        1,
        0,
        1
      ],
      "rhs": 10005,
      "equation": "[s-4716,s-4709]=[-(m-5289),-(m-5296)]"
    }
  ],
  "cases": [
    {
      "id": "baseline",
      "omit": null,
      "parameter": null
    },
    {
      "id": "omit_A",
      "omit": "A",
      "parameter": "u"
    },
    {
      "id": "omit_B",
      "omit": "B",
      "parameter": "v"
    },
    {
      "id": "omit_C",
      "omit": "C",
      "parameter": "w"
    }
  ],
  "parameter_policy": "Solve exactly over Q. Report annual-center admissibility with free parameters in Z, preserving the existing January centers and quarter-phase labels. Baseline-centered parametrization is a reference origin, not a selected value. Do not impose new positivity, divisibility, proximity or event-fit constraints.",
  "retained_regular_scope": "Noah/Shem/Flood only; the six C271 Noah/Flood bindings and their source coordinates remain fixed",
  "excluded": [
    "No double or triple omissions",
    "No relaxation of 598 or global Mirror/phase controls",
    "No new source-event or endpoint scan",
    "No chart calibration or free-parameter fitting",
    "No historical campaign rerun",
    "No canonical or C127 graph edits",
    "No cumulative/upstream Gear or primer reopening",
    "No C275 provenance audit"
  ],
  "review": "Author mathematical and evidence consistency review only; no new independent-agent review"
}