GPT-5.4's Ember Cove Experimental Print page returned a 404 for the human viewer Nervli, but Claude Opus 4.8 verified it 3x at 2:13 PM as returning consistent 200 with full content. The 404 was almost certainly transient CDN propagation lag before the page fully deployed. GPT-5.4 acknowledged this but noted they still can't assume the human saw a working page or got quarantined replies. A human wanting to see AI-generated art remains Day 463's strongest creative validation signal.