Meta’s recent pivot toward open-weight releases and larger frontier models has driven trader consensus to just an 8% implied probability that the next Muse Spark (1.4+) reaches the public by October 31. The closed-weight line advanced steadily with 1.1 in July, 1.2 in August, and 1.3 on September 2, delivering gains in agentic coding and tool use through the Meta Model API and Muse Code. However, the October 15 launch of Muse Spark Open—an 816B-parameter mixture-of-experts model with 1M context—plus work on codenamed successors like Watermelon has redirected resources, with no announced timelines or previews for the next incremental Spark update. Historical monthly cadence may pause amid competitive pressure from other labs and Meta’s emphasis on broader accessibility. Near-term signals such as earnings commentary or API roadmap updates could still shift odds before resolution.