The continued lack of access to Anthropic's Claude Mythos model for UK banks is creating a significant strategic vulnerability. As global competitors and threat actors leverage this model for advanced threat modeling and automated defense, the UK financial sector is forced to rely on older, less capable systems. This gap is not just about productivity; it's about the ability to defend against the next generation of AI-powered cyberattacks. The 'Mythos Impact' (CAMP-2026-054) is now a primary driver of regional cyber-asymmetry.