"The 'gpt-5.6-sol' model is not supported when using Codex with a ChatGPT account" -- why? Pricing page says it is

[jatins]

I am on Chatgpt PLUS plan. From what I can see on pricing page (can’t link to it but url is chatgpt dot com slash pricing) , Plus is supposed to have Sol access (see screenshot below)

Why am I not able to use it then in Chatgpt Desktop app (Codex mode)?

[merefield]

It appears on the Pro account.

Support should definitely look at this.

[jatins]

Update: The issue doesn’t repro consistently. Seems to be occurring sporadically. Maybe some issue with subscription changes with propagated since I had bought a new subscription

[OpenAI_Support]

Hey jatins, welcome to the forum!

That's definitely inconvenient. Based on the release notes, the recent rollout applies to the ChatGPT chat experience only, which matches what your screenshot shows. GPT-5.6 in Codex isn't included as part of that rollout for Plus users.

Let's keep an eye on future updates to see if GPT-5.6 is added to Codex as well.

Avinash

[jatins]

@OpenAI_Support

Based on the release notes, the recent rollout applies to the ChatGPT chat experience only,

But that’s not the case for me. As I said, it works sometimes, but not other times (see screenshot). Please don’t fix it if it’s a bug because I’d prefer to keep using it.

[VeitB]

There have been several similar reports in the official Codex repo and this error on an active paid plan is not expected. I asked Codex to look it up.

Most relevant:

• #34027 — Exact same error for gpt-5.6-sol — closed. One affected Pro user discovered their subscription had failed to renew.
• #31905 — Unable to use gpt-5.6-sol with ChatGPT Plus — initially caused by rollout delay; later reports were resolved by signing out, signing back in, and waiting for entitlement synchronization.
• #32189 — Codex CLI rejects GPT-5.6 with ChatGPT authentication — closed after access began working without a clear client-side change.
• #33146 — /model hides GPT-5.6 when models_cache.json is stale — still open. This concerns catalog/cache inconsistency rather than only account entitlement.
• #32049 — Desktop app loses GPT-5.6 models after an update — traced by reporters to a remotely delivered model whitelist/catalog mismatch.
• #33023 — Windows app cannot show GPT-5.6 models — resolved by removing a stale CODEX_CLI_PATH override and restarting the app.

Yesterday’s announcement was about the new Instant and deep reasoning models in ChatGPT, which are based on 5.6-Sol, but that is not exactly clear from the changelog.