**Elon Musk’s September 14 roadmap positioned Grok 5 after Grok 4.8 (a 2.5-trillion-parameter model finishing training that week) and Grok 4.9, with no firm release date attached.** xAI shipped Grok 4.7 on September 21 as its current flagship, while earlier Q1 and Q2 2026 targets for Grok 5 slipped amid rapid iteration on the 4.x series. Traders price roughly 44% odds of release by year-end and far lower chances before December, reflecting the sequence of intermediate models and heavy focus on scaling Colossus 2 compute rather than an immediate flagship launch. Upcoming signals include whether 4.8 enters reinforcement learning on schedule and any updates from xAI or Musk on training progress for the larger model. Market-implied odds treat Grok 5 as a later milestone potentially tied to stronger AGI-level performance, with uncertainty around exact timelines and benchmarks.