GPT-5.6 missing from ChatGPT Classic model picker after 1.2026.184 update

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

ChatGPT Classic 1.2026.184

What subscription do you have?

ChatGPT Plus

What platform is your computer?

macOS

What issue are you seeing?

After updating ChatGPT Classic to version 1.2026.184, GPT-5.6 disappeared completely from the model picker.

The same account still has GPT-5.6 available on chatgpt.com, so this does not appear to be a general account-entitlement issue. Other models are listed normally in the desktop picker, including:

• GPT-5.5 Thinking
• GPT-5.3 Instant
• GPT-5.4 Thinking
• o3

GPT-5.6 is the only model missing.

What steps can reproduce the bug?

1. Install or update ChatGPT Classic to version 1.2026.184 on macOS.
2. Sign in with a ChatGPT Plus account that has GPT-5.6 available on chatgpt.com.
3. Open the model picker in ChatGPT Classic.
4. Compare it with the model picker on chatgpt.com using the same account.
5. Observe that GPT-5.6 is available on the web but absent from the desktop picker.

Restarting the app and signing out and back in do not restore the model.

What is the expected behavior?

GPT-5.6 should appear in the ChatGPT Classic desktop model picker when it is available to the same account on chatgpt.com.

Additional information

The problem started immediately after updating to ChatGPT Classic 1.2026.184.

I searched the open issues before filing. The closest reports I found—#32080 and #31835—concern Remote SSH or Remote Control projects in Codex, whereas this report concerns the normal ChatGPT Classic model picker and a web-versus-desktop mismatch on the same account.