I did and it couldn’t find evidence of Anthropic backtracking on Mythos fear mongering. I used Grok given it has access to all Twitter data and these kind of things would have been newsworthy on Twitter. The most I could find is this report showing Mythos isn’t any more groundbreaking that GPT 5.5. https://www.aisi.gov.uk/blog/our-evaluation-of-openais-gpt-5...
If you or anyone had any evidence to support GP’s claim I’d love a reference to it.