[BUG] Sonnet 4.6 1m missing from Max plan

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Sonnet 4.6 1m is not available: just the 200k context version.
Trying to force it with /model gives the error --> not included in the plan.

What Should Happen?

Sonnet 4.6 1m must be the default for the max plan

Error Messages/Logs

Sonnet 4.6 with 1M context is not available for your account. Learn more:
     https://code.claude.com/docs/en/model-config#extended-context-with-1m

Steps to Reproduce

1. Enter the interface
2. /model
3. select sonnet 4.6
4. /context --> context is 200k
5. /model sonnet[1m]
6. Error Sonnet 4.6 with 1M context is not available for your account. Learn more:

https://code.claude.com/docs/en/model-config#extended-context-with-1m

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

v2.1.195

Platform

Other

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Other

Additional Information

Terminal Gostty
Claude Code CLI