According to Google, in their blog post introducing SynthID text watermarking:

This summer, we’re planning to publish more about our text watermarking technology in a detailed research paper, and we’ll open-source SynthID text watermarking through our updated Responsible Generative AI Toolkit, which provides guidance and essential tools for creating safer AI applications, so developers can build with this technology and incorporate it into their models.

October is defined relative to Pacific Daylight Time (PDT) as that's where Google's headquarters is located.

By open-source, I roughly mean that they give instructions/code that would allow someone to apply SynthID watermarking to gpt-2 or another open-source LLM.

If they publish a research paper but they don't open-source SynthID, resolves NO.