# Type 212 Submarine revision history

Append-only Arc G field-change log. Forward-only honesty: events accrue from Arc G adoption.

Model: [Type 212 Submarine](/models/type-212.md)

_No events on file. Arc G is forward-only; the recorded event log accrues from Arc G adoption (2026-06-04) and records material changes as they flow through the updateEntityField chokepoint. For the current state of this model, see the model page._

## Forward-only note

Arc G is forward-only. The event log accrues from the Arc G adoption point. Fields with no events post-baseline equal the current cached value and are not independently verified at any prior date. To restate a recorded change, write a new event through the updateEntityField chokepoint.

_Canonical URL: /models/type-212/history. REST: /v1/models/cd8fcad8-d66d-4acc-a283-7ae47f2020f5/history. HTML: [/models/type-212/history](/models/type-212/history)._