Some ChatGPT users have reported simultaneous performance improvements and response delays, fuelling speculation that OpenAI is privately testing GPT-5.6. Posts on X described results that appeared different from GPT-5.5 Pro on paid accounts, including better web design and 3D game outputs but much longer processing times. Developers and influencers shared comparisons, while other tests found no clear advantage. OpenAI has not confirmed anything, and the model’s release remains uncertain.

U.S. defense technology startup Mach Industries raised $300 million in a Series C round, valuing the company at $1.8 billion. TechCrunch reported the valuation is nearly four times higher than a year ago, after a $100 million raise in June 2025 at a $470 million valuation. The round was led by Infinite Capital and Ribbit Capital. Mach is developing five autonomous aircraft and plans to start producing at least three next year.