Thirty days since Opus 5, against twenty-one between Fable 5 and Sonnet 5 and twenty-four from there to the Opus release on 24 July. One tracker puts the house average at about every 24 days and still shows its next projection as 17 August, six days expired and never recalculated. That is about what cadence models are worth once a lab decides to sit on something.

The Polymarket-derived forecasts, regenerated today, put Anthropic's next Mythos-class model at a median of 15 September and Astra at 19 September. Anthropic first, by four days, which runs backwards to the story everyone has been repeating, me included.

Then I looked at the curves rather than the medians. Astra's reaches 90% by the end of October. Anthropic's reaches 55% and stops, having crossed the halfway line on 15 September and gained five points between then and the end of October. That is not a forecast of a release date. It is a book that runs out of people willing to price it, and there is no contract at all on the model the reporting is actually about.

So: late September, OpenAI first, Anthropic within days of it. I'm backing the leak over the aggregate, mostly because on Anthropic's side there is no aggregate to argue with.

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