OpenAI cuts GPT-5.6 Luna prices by 80%, Terra by 20%

GPT-5.6 Luna now costs $0.20 per million input tokens and $1.20 per million output, an 80% drop; Terra is down 20% to $2/$12. GPT-5.6 Sol gains a 2.5x faster API mode at 2x price. OpenAI credits Sol with optimizing inference, cutting serving costs by 20%.