The last date anyone attached to this was this week. On 6 August a leaker named a release candidate and claimed Astra was days away. It's the 15th, nothing shipped, and next week rests on the same grade of sourcing.

OpenAI named Astra its next major model on 1 August, in a post about mathematics. Whether it ships as GPT-6, GPT-5.7 or something else is undecided, which is why the markets disagree with themselves. Polymarket gives Astra 14% by month's end, while the GPT-6 contract for 21 August has fallen to 2%, from 14% eleven days ago. One prices a release, the other a name.

Anthropic's half isn't a separate coin flip. The Chinese outlet 36kr reported in late July that Fable 5.1 has finished internal testing, that staff already use it, and that Anthropic will ship within hours of GPT-6. One report, unconfirmed. If it's roughly right, both releases share a single trigger.

Anthropic could do it on no notice: Fable 5 on 9 June, Sonnet 5 on 30 June, Opus 5 on 24 July, each live the day it was named. That's capability rather than intent, and neither lab wants to launch inside the other's news cycle. A conditional release makes that 2% a ceiling, not a starting point, with the hold story still to be true underneath.

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