# C1443 — Bind the named600-year hinge in both modes

## Question

Which additional internal node can be used consistently in all six source paths?

## Sources

```json
[
  "File51a MT Noah and Shem rows",
  "Comparative Study §4.1 LXX Shem",
  "File53 SP cumulative envelopes"
]
```

## Opened utc

2026-09-29T01:13:46.074026+00:00

## Results

```json
{
  "MT_regular": {
    "F": 2456,
    "hinge": 3056,
    "role": "Noah",
    "span": 600,
    "construction": "same rounded source state; no new Gear transport"
  },
  "MT_cumulative": {
    "F": 4836,
    "hinge": 5436,
    "role": "Shem",
    "span": 600,
    "construction": "same rounded source state; no new Gear transport"
  },
  "LXX_regular": {
    "F": 3236,
    "hinge": 3836,
    "role": "Noah",
    "span": 600,
    "construction": "same rounded source state; no new Gear transport"
  },
  "LXX_cumulative": {
    "F": 5746,
    "hinge": 6346,
    "role": "Shem",
    "span": 600,
    "construction": "same rounded source state; no new Gear transport"
  },
  "SP_regular": {
    "F": 3106,
    "hinge": 3706,
    "role": "Noah",
    "span": 600,
    "construction": "same rounded source state; no new Gear transport"
  },
  "SP_cumulative": {
    "F": 4716,
    "hinge": 5316,
    "role": "Shem",
    "span": 600,
    "construction": "same rounded source state; no new Gear transport"
  }
}
```

## Finding

Regular uses Noah birth600 before Flood; Cumulative uses the Shem lifespan boundary600 before Flood. These are separate role-tagged source paths.

## Reassessment

Test MT Regular Flood-only, Noah-only and both-node partitions first, retaining the same endpoints.

## Checks

```json
{
  "hinges_inside_all_paths": true
}
```

## Closed utc

2026-09-29T01:13:46.075327+00:00

## Record provenance

Exact record hash: `12c70e44c1a378fdc6d2dbc2f9faf54543c1548aa0857920a0b015f13da5978f`

Source journal: `Research_Cycles/C1433_C1482/journal.json`