{
  "number": 389,
  "date": "2026-09-24",
  "title": "Cumulative source test of the reflected E/J square",
  "question": "Do the two existing17K corner exchanges give source-qualified cumulative counterparts for the new regular E/J squares?",
  "authorization": "User authorized next10 bounded steps C384–C393; next question reassessed after each completed result.",
  "scope": "Mirror/529; regular Gears Noah/Shem/Flood only; SP companion local. Fixed source inputs, no canonical/graph changes."
}