Anthropic’s next Mythos-class model faces a tight September release window because prior training cycles aligned with roughly three-month intervals after major compute upgrades at its New Carlisle cluster, while US regulatory oversight and internal safety classifiers continue to shape rollout timing. Market-implied odds remain clustered between 22–26% across mid-to-late September dates, reflecting trader consensus that Anthropic must balance demonstrated cybersecurity capabilities against government export controls and competitive pressure from OpenAI’s phased GPT-5.6 family. Key swing factors include any new Project Glasswing partner announcements, safeguard refinements for biology or model-distillation queries, and whether the company opts for a limited Fable-style public variant or fully restricted Mythos edition. Earnings calls and partner briefings in early September could shift sentiment quickly.