OpenAI Releases ChatGPT and Codex Build 26.908.70816 After GPT-6 Astra Performance Complaints

Days after the release of GPT-6 Astra, some users reported that the model had suffered a degradation in performance. Feedback was particularly concentrated among Chinese-language users, some of whom said they had been routed to lower-tier models and saw a decline in performance. Some paying users also encountered similar problems. Some users outside China reported difficulty connecting, with a comparatively milder degree of degradation.

OpenAI has begun addressing the performance degradation of GPT-6 Astra. On September 15, 2026, OpenAI pushed ChatGPT and Codex build 26.908.70816. Some users reported that the build alleviated part of the degradation, though the problem has not been fully resolved.

Questions that can be used to detect degradation in GPT-6 Astra include knowledge cutoff dates and a cormorant riding a bicycle. A separate detection page sets three random challenges; users paste GPT-6 Astra's answers back into the page to analyze whether the model has degraded. The detection method is related to the particular style that large models exhibit when generating random numbers, and is used to identify a model's true identity. The page is designed only for GPT-series models.