OpenAI has historically released major model versions on irregular schedules. GPT-4 launched in March 2023, GPT-4 Turbo in November 2023, and GPT-4o in May 2024. The question of when GPT-5.5 will arrive has become a focal point for AI traders and market participants anticipating the next major capability leap. April 27, 2026 represents a specific release date prediction window. This market is resolvable through official OpenAI announcements, website updates, or verified press releases confirming a GPT-5.5 launch on that exact date. The current market price of 1% YES suggests traders view a mid-April 2026 release as extremely unlikely at this moment. The asymmetric odds reflect widespread expectation that OpenAI will either release significantly earlier, later, or use different version numbering. Markets on AI model release timing have historically shown strong correlation with public roadmap signals, developer conference announcements, and competitive pressures from rival AI labs. The upcoming weeks may reveal new information through earnings calls, research papers, or unofficial developer channels that shift probabilities. Trade this prediction market if you believe GPT-5.5 will launch precisely on April 27, or position inversely if you think the actual release will deviate from that date.