[BUG] Billing: ~€85 promotional credit disappeared without usage (Max 5x, April 2026 promo)

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?

My one-time promotional extra usage credit (~$100 / ~€85) from the April 2026 promo disappeared after upgrading from Max 5x to Max 20x.

Timeline:

• Before April 17, 2026: Claimed the one-time credit via claude.ai/settings/usage (~$100 for Max 5x plan)
• Credit visible: ~€85 shown in Extra Usage balance
• Plan upgrade: Changed from Max 5x ($100/mo) to Max 20x ($200/mo)
• Current state: Balance dropped to ~€10 immediately after upgrade — credits were NOT consumed

What Should Happen?

Promotional credits should be preserved when upgrading plans. The credit was validly claimed before the April 17 deadline and should remain valid for 90 days regardless of plan changes.

Error Messages/Logs

Steps to Reproduce

1. Subscribe to Claude Max 5x plan ($100/month) before April 3, 2026
2. Claim the one-time promotional extra usage credit (~$100) via claude.ai/settings/usage before April 17, 2026
3. Verify credit balance shows ~$100 / ~€85
4. Upgrade plan from Max 5x to Max 20x via claude.ai/settings/billing
5. Check Extra Usage balance after upgrade
6. Result: Credit balance drops to ~$10 — promotional credit is wiped without warning or consumption

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude Code Version N/A — this is a claude.ai billing issue, not a Claude Code bug. Filing here as Anthropic routes billing issues through this repo (see related issues #23674, #47210, #56338).

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

This is the same billing system bug as:

• #23674 — Credits disappeared after subscription renewal
• #47210 — Promotional credit lost after plan lapse
• #56338 — Credit disappeared after Pro→Max upgrade