[BUG] Max 20x: Extra usage balance ($15) not consumed for Sonnet/Opus — OAuth token gets 429 while Haiku works

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report
• [x] I am using the latest version of Claude Code

What's Wrong?

Environment: macOS (Darwin 25.3.0), Max 20x plan ($200/month), subscribed April 3 2026
Organization ID: 49813ced-76fa-4118-adbc-5f6d56ecefb0

Setup:

• Extra Usage: ENABLED
• Balance: $15.00 (loaded via credit card)
• Spending limit: $26
• Auto-reload: ON

What happens:

OAuth token (sk-ant-oat01-*) obtained via claude setup-token returns different results per model:

| Model | HTTP | Response |
|-------|------|----------|
| claude-haiku-4-5 | 200 OK | Works, balance NOT consumed |
| claude-sonnet-4-6 | 429 | {"type":"rate_limit_error","message":"Error"} — no retry-after header |
| claude-opus-4-6 | 429 | Same as Sonnet |

The $15 balance is never consumed. Sonnet/Opus are hard-blocked (429 with no retry-after, not a real rate limit).

Previously the error was HTTP 400:

"Third-party apps now draw from your extra usage, not your plan limits. 
We've added a $200 credit to get you started. Claim it at claude.ai/settings/usage"

The "$200 credit" claim banner does NOT appear anywhere:

• Not on claude.ai/settings/usage
• Not on claude.ai/settings/billing
• Not on claude.ai main chat page
• Not in Claude Desktop app
• Tried Safari, Chrome, iPhone — no banner in any browser
• Tried logging out/in — no change

Likely cause: Account subscribed April 3 (on the cutoff date), so the promotional credit may not apply. But the $15 loaded balance should still allow Sonnet/Opus access through extra usage. The system gates Sonnet/Opus on the promotional credit claim flag, ignoring the actual balance.

What Should Happen?

My $15 extra usage balance should be consumed when third-party apps call Sonnet or Opus. The 429 should only occur when balance reaches $0, not when a promotional credit hasn't been claimed.

Related Issues

• #45013 — 100% failure rate, same error
• #45134 — Max $200/month blocked, claim didn't help
• #45027 — Same erroneous extra usage detection
• #45021 — Same billing error despite remaining quota

Steps to Reproduce

1. Subscribe to Max 20x
2. Enable extra usage, load $15 balance
3. Obtain OAuth token via claude setup-token
4. Call Anthropic API with claude-sonnet-4-6 model using OAuth token
5. Receive 429 — balance not consumed

Claude Model

claude-sonnet-4-6, claude-opus-4-6

Is this a regression?

Yes — before April 4, 2026, OAuth tokens worked for all models under subscription limits.