OpenAI has not publicly announced a GPT-5.5 release as of April 2026. The company's recent model releases have followed unpredictable timelines: GPT-4 launched in March 2023, GPT-4 Turbo in November 2023, and GPT-4o in May 2024. While GPT-5 is widely anticipated as the next major milestone, whether an intermediate GPT-5.5 version will exist, and when it might arrive, remain open questions. The current market odds of 2% reflect strong trader skepticism that any release would occur within the 48 hours remaining before the April 19 deadline. This low probability assignment suggests traders believe a GPT-5.5 announcement either will not happen at all, or will not occur until after this market closes. Resolution is determined by a single objective criterion: OpenAI must publicly announce GPT-5.5 availability through official channels before midnight UTC on April 19, 2026. Any announcement after that timestamp results in a NO resolution. With just $942 in 24-hour volume, liquidity is modest, indicating limited retail interest in this outcome. Most traders are positioned for a NO result, reflecting widespread expectations that the company will not release such a version imminently.