# C1142 — Explain the Methuselah249 reduction by local changes

## Question

Which pieces of the retained source shift produce249 rather than250?

## Inputs

```json
{}
```

## Sources

```json
[
  "C1141",
  "File18 §§2.1.3,3.1"
]
```

## Opened utc

2026-09-28T05:01:15.642695+00:00

## Results

```json
{
  "local_reduction": {
    "path": "model/Methuselah_reduction_decomposition.json",
    "sha256": "9613acc437399d19ecf7d394e9e7031aab6d0633eac1ad3bb00846c643bcb5fc",
    "bytes": 299
  },
  "reduction": 249
}
```

## Finding

The249 reduction is120+130−1: two local age changes and one count-convention difference. Using the ordinal53 label gives129 at that stage, but the completed52 primary path must not receive a second correction.

## Reassessment

Place all nine ancestral rows on the same capacity-and-slack comparison.

## Checks

```json
{
  "exact_reduction": true,
  "same_primary_count": true,
  "ordinal_identity": true
}
```

## Closed utc

2026-09-28T05:01:15.642998+00:00

## Record provenance

Exact record hash: `e9b892f41e1032aae886ae8f4f531d760f84364db14ed4785ea813d2e7d627fc`

Source journal: `Research_Cycles/C1132_C1431_Recovered/journal.json`