# C808 — Construct the BJ–NT2450 duration interface

## Question

Do two complete source constructions measure the same span through different carriers?

## Inputs

```json
{}
```

## Sources

```json
[
  "File43 §4; File20/53 BJ2450"
]
```

## Opened utc

2026-09-28T02:09:00.452823+00:00

## Results

```json
{
  "Luke_head": 5326,
  "Matthew_envelope_head": 2876,
  "difference": 2450,
  "measurements": {
    "generation_carrier": 2450,
    "jubilee_carrier": 2450
  },
  "status": "duration equality, not event identity or direct literary-dependence proof"
}
```

## Finding

The declared heads generate5326−2876=2450, measured as35×70 and50×49. The bridge joins duration constructions while retaining their different source roles and indices.

## Reassessment

Test the head-role discriminator and close the BJ transfer.

## Checks

```json
{
  "source_heads": true,
  "same_duration": true
}
```

## Closed utc

2026-09-28T02:09:00.453697+00:00

## Record provenance

Exact record hash: `86575adc2953989ee63f60b177af700be3f7544500d1875fb49f7c1eee8983ce`

Source journal: `Research_Cycles/C0732_C0831/journal.json`