[Windows App] GPT-5.6 available in Chat but missing from Work and Codex model pickers

What version of the Codex App are you using (From “About Codex” dialog)?

26.730.61639

What subscription do you have?

ChatGPT Plus

What platform is your computer?

Microsoft Windows 11 x64

What issue are you seeing?

GPT-5.6 model availability is inconsistent across product surfaces when using the same ChatGPT Plus account and workspace.

Observed model availability:

1. ChatGPT web:

• GPT-5.6 is available in Chat mode.
• GPT-5.6 is available in Work mode.

1. ChatGPT Windows app, version 26.730.61639:

• GPT-5.6 is available in Chat mode.
• GPT-5.6 is not available in Work mode.
• GPT-5.6 is not available in Codex.

In the Windows app, the Work and Codex model pickers show only older models, including GPT-5.5, GPT-5.4, and GPT-5.4 Mini.

Because GPT-5.6 is available in the Windows Chat surface and in both Chat and Work on the web using the same account, this does not appear to be a general account-entitlement problem. It appears that the Windows app is receiving or using a different, incomplete, or stale model catalogue for the Work and Codex surfaces.

What steps can reproduce the bug?

Feedback ID: no-active-thread-019fd84a-408a-7db0-921f-27ab2fd701c1

What is the expected behavior?

The Windows app should expose the same GPT-5.6 model entitlement and model catalogue across Chat, Work, and Codex when those models are available to the same authenticated account.

Since GPT-5.6 is available in Chat within the Windows app and in both Chat and Work on the web, GPT-5.6 should also be listed and selectable in the Windows Work and Codex model pickers.

Additional information

This appears to be specific to the model catalogue or entitlement synchronization used by the Work and Codex surfaces in the Windows app.

The same Windows application successfully displays GPT-5.6 in Chat mode, which indicates that:

• The application is authenticated correctly.
• The account has GPT-5.6 access.
• The Windows app can access GPT-5.6 in at least one surface.
• The failure is isolated to Work and Codex model discovery or filtering.

App version: 26.730.61639
Subscription: ChatGPT Plus
Affected surfaces: Windows Work and Windows Codex
Unaffected surfaces: Windows Chat, web Chat, and web Work

I can provide screenshots showing:

1. GPT-5.6 available in web Work.
2. GPT-5.6 available in Windows Chat.
3. GPT-5.6 missing from the Windows Work and Codex model pickers.