Why OpenAI Shipped GPT-5.5 Just 6 Weeks After 5.4

Six weeks. That's how long it took OpenAI to ship GPT-5.5 after 5.4. Until this year, frontier labs did that in quarters. GPT-5.5 is OpenAI's latest flagship language model, codenamed Spud, released April 23, 2026 — 6 weeks after GPT-5.4. The name "S...