# Master Index 6.4.2.7 - Structural Records Directory Transition

Date: 2026-09-01

## Status

Repository-settled public-surface transition record.

## Summary

The former Threshold Queue / Backlog Queue live public identity was superseded by
the Structural Records Directory.

## Basis

The preceding responsibility and nomenclature review found that:

- Master Index remains the repository-settled current-state authority.
- Atlas remains the broad public orientation and traversal district.
- Card Catalog, Corpus Position Index, Artifact Index, Publications, topology
  records, manifests, schemas, provenance records, procedural records, and
  verification records already hold specialized responsibilities.
- No single public surface cleanly answered which structural record system
  should be consulted for a specific class of structural fact.

## Transition

- Former live card/page identity: Threshold Queue / Backlog Queue.
- Former live route: `/apex/backlog.html`.
- New live card/page identity: Structural Records Directory.
- New live route: `/apex/structural-records.html`.

No compatibility requirement for preserving `/apex/backlog.html` as a live route
or redirect was observed during the transition audit.

## Authority Boundary

The Structural Records Directory is derivative and navigational only. It does
not determine current canonical or operative Quasantum state, does not replace
the Master Index, and does not absorb Atlas, Card Catalog, Corpus Position
Index, Artifact Index, Publications, relation, field, governance, or procedural
record responsibilities.

## Preservation

Historical uses of Threshold Queue, Threshold Q, Backlog Queue, and
`/apex/backlog.html` remain factual archaeology where they document prior work,
candidate studies, route observations, or publication manifests. They no longer
name a current live public district.