Leaked reports of a fresh pretraining run for Anthropic’s Fable line, first surfaced in early September, have anchored trader expectations for a 5.2+ release in early October. Community observations of Fable 5.1 routing to an unidentified newer model inside Claude Code, plus Anthropic’s September 22 rollout of Sonnet 5.5 and Haiku 5.5 without a corresponding Fable update, have reinforced the view that the next frontier model is in final testing. The tight clustering of market-implied odds around October 5–8 reflects uncertainty over exact internal milestones, regulatory review timing, and whether Anthropic will bundle the launch with additional capability or pricing announcements.