**Anthropic’s September 22 announcement of Claude Haiku 5.5 “in the coming weeks” after the Opus 5.5 launch, followed by Sonnet 5.5’s September 28 release, is the main catalyst behind the market’s mid-October clustering.** Traders see the “weeks” window and Haiku 4.5’s approaching deprecation (not sooner than October 15 on the Anthropic API) as aligning with the company’s pattern of rolling out the lightweight tier shortly after Sonnet updates. The tight spread across October 12–24 outcomes, with October 21 leading at 28.5% implied probability, reflects uncertainty over exact timing amid ongoing 5.5-family optimizations for speed, cost, and safety rather than any confirmed internal milestone. No release by October 31 sits at just 10.5%, underscoring broad consensus on an imminent launch while leaving room for last-minute delays common in frontier-model deployments.