OpenAI: GPT-5.6 Sol limited preview under U.S. government coordination
freshWhat moved: OpenAI launched a limited preview of GPT-5.6 Sol (flagship), Terra (balanced, 2x cheaper than GPT-5.5), and Luna (fast/affordable). Access is restricted to trusted partners via API and Codex only — not ChatGPT — at the request of the U.S. government. OpenAI publicly pushed back, saying this access process "should not become the long-term default."
Why it matters: Government-gated model releases are now precedent. The "ultra" mode uses subagents for complex work, and Sol sets SOTA on Terminal-Bench 2.1. Pricing: Sol $5/$30, Terra $2.50/$15, Luna $1/$6 per 1M tokens. New prompt caching with explicit breakpoints and 30-min minimum cache life.