MODEL LIFECYCLE · ACTION DESK

A launch is news. A shutdown is a deadline.

Track releases, preview access, deprecations, retirements and replacement paths without mixing ChatGPT product availability with API availability.

5available / preview

3migration watch

4providers tracked

100%primary sources

Watch

Anthropic

Claude API

Claude Haiku 4.5

No retirement before 2026-10-15

Active today; October 15 is the current earliest-retirement commitment boundary.

Next action

Prepare a small latency, price and quality regression suite before any lifecycle announcement lands.

Official source ↗Checked 2026-09-0414d

Available

Google

Gemini API

Gemini 3.7 Flash

Intro pricing ends 2026-12-31

The latest Flash line emphasizes coding and agentic tasks. Its introductory API price is time-bounded.

Next action

Benchmark before and after removing deprecated sampling parameters; include the post-promotion price in cost projections.

Official source ↗Checked 2026-09-0491d

Deprecated

Google

Gemini API

Gemini 3.1 Flash-Lite

Earliest shutdown 2027-05-07

A stable endpoint with a documented shutdown horizon and a recommended successor.

Replacementgemini-3.5-flash-lite

Next action

Plan a controlled migration to Gemini 3.5 Flash-Lite well before the earliest shutdown date.

Official source ↗Checked 2026-09-04218d

Watch

Anthropic

Claude API

Claude Sonnet 4.5

No retirement before 2026-09-29

Still active. September 29 is an earliest-retirement commitment boundary, not an announced shutdown date.

Next action

Inventory pinned model IDs now and subscribe to official deprecation notices; migrate only after a replacement is documented and tested.

Official source ↗Checked 2026-09-04

Limited

OpenAI

ChatGPT + Codex + API + cloud partners

GPT-6 Astra

Rolling out from 2026-09-03

OpenAI's new flagship is initially available to a limited set of organizations, with broader ChatGPT, API, Azure and Bedrock access rolling out over the following days.

Next action

Run a task-level regression suite before changing defaults. Keep OpenAI's benchmark claims separate from independently reproduced results.

Official source ↗Checked 2026-09-04

Limited

OpenAI

Daybreak · restricted access

GPT-5.6-Cyber

Announced 2026-08-10

A cybersecurity-specific model available through the Daybreak program for approved defensive use cases.

Next action

Treat access and safeguards as part of the product surface; do not compare it as if it were an unrestricted public API.

Official source ↗Checked 2026-09-04

Preview

World Labs

Research preview + early access

Atlas

Announced 2026-09-01

An omni world model spanning text, image, video and 3D in one spatial context, with generation, reconstruction and real-to-sim demos.

Next action

Follow capability access separately from demo quality; weights and a general public API are not currently documented.

Official source ↗Checked 2026-09-04

Available

OpenAI

ChatGPT + Codex + API

GPT-5.6 · Sol / Terra / Luna

Pricing updated 2026-08-21

The three-tier GPT-5.6 family is generally available. Sol is the flagship, Terra balances capability and cost, and Luna targets speed and price.

Next action

Re-run one representative workload across all three tiers; compare task success and total token cost, not list price alone.

Official source ↗Checked 2026-09-04

Retired

Anthropic

Claude API

Claude Opus 4.1

Retired 2026-08-05

API requests to Claude Opus 4.1 no longer work; Anthropic recommends Claude Opus 4.8.

Replacementclaude-opus-4-8

Next action

Replace the exact model ID, rerun regression evaluations and compare changed sampling-parameter behavior.

Official source ↗Checked 2026-09-04

Retired

Google

Gemini API

Embedding 2 Preview

Shut down 2026-08-10

The preview endpoint has shut down; the stable Gemini Embedding 2 endpoint is the recommended replacement.

Replacementgemini-embedding-2

Next action

Re-embed a representative slice and measure retrieval drift before replacing a production vector index.

Official source ↗Checked 2026-09-04

Retired

OpenAI

ChatGPT only

GPT-4o / GPT-4.1 / o4-mini / GPT-5.1

Retired by 2026-03-11

These ChatGPT choices were retired; the same names may still have different API availability. Product and API lifecycle are tracked separately.

ReplacementGPT-5.3 Instant / GPT-5.4 Thinking and Pro

Next action

Audit saved prompts and Custom GPT behavior against the current GPT-5.3 / GPT-5.4 equivalents.

Official source ↗Checked 2026-09-04

A 'no retirement before' date is a commitment boundary, not a confirmed shutdown. Always re-open the official source before a production migration.