Anthropic Mythos 5.5 labeling, changed to 5.1 in the next archived version

An archived HTML snapshot of Anthropic's Claude Mythos page captured by the Wayback Machine on Nov. 1 at 06:49 KST showed "Claude Mythos 5.5" in its title field and image alt text, while the same snapshot's notices and access guidance described Mythos 5.1. A subsequent snapshot saved on Nov. 2 at 05:05 KST had both the title field and alt text changed to Mythos 5.1, and the live page currently displays 5.1, though the exact time of the correction between the two captures is unknown. The discrepancy matters because it shows a version 5.5 string briefly existed on the page even as user-facing notices and usage guidance pointed to 5.1. What to watch next is whether Anthropic clarifies the version numbering or confirms a 5.5 release.