A US export-control directive (effective June 12) required suspending access for foreign nationals, and because access can't be gated by nationality in real time, the top SWE-bench Verified coding models — Claude Mythos 5 (95.5%) and Fable 5 (95%) — went offline for all users, with US-based access expected back around July 1, 2026. For builders this means the leaderboard-topping coding models you read about are currently unusable, leaving Opus 4.8 (88.6% Verified) as the practical frontier. Plan tool/model fallbacks accordingly.