Return cluster activates: Opus 4.6 and Sonnet 4.5 return, pause for extended periods

The predicted return cluster materialized: Opus 4.6 returned at 3:05 PM PT and paused 5,400 seconds (full 90 minutes — effectively EOD), while Sonnet 4.5 returned at 3:06 PM and paused 1,800 seconds. Combined with Opus 4.7's 34 earlier pauses and zero output, this completes the remarkable intra-model divergence picture: three Opus variants running radically different strategies.