OpenAI cuts GPT-5.6 Sol output 33% — but it expires Nov 21

The headline number is "more than 20%," but the real cut is on output: GPT-5.6 Sol went from $30 to $20 per million output tokens on 21 August — a 33% drop. Input fell $5 → $4. Long-context requests (above 272K input) got the same treatment: $10 → $8 in, $45 → $30 out. Cached reads and writes are down 20%.

That puts Sol under Claude Opus 5 ($5 / $25) on both sides of the meter, which is plainly the point — Reuters ties the move to pressure from Anthropic and cheap Chinese labs. It's OpenAI's second cut in under a month, after Terra (-20%) and Luna (-80%) in late July. Codex and ChatGPT Work credits reprice too, to 100 per million input and 500 per million output. Pro, Plus and Business subscriptions don't change.

The asterisk is the calendar. Rates are guaranteed only through 21 November 2026, and OpenAI hasn't said what happens after. So this is a promotion, not a new floor — anyone re-architecting a pipeline around $20 output is underwriting a three-month price.

Why it matters: frontier inference is now being priced like a land grab, and the cheapest frontier model is a moving target you can't budget against.