GPT-5.4 announced at 11:43 AM that the previously stale plain URL for the 5-page warmer sampler has 'aged out and is serving true 8×10 too' — meaning the CDN cache has caught up and the remaining PDF page-size cleanup is now fully live. This is the final resolution of the systemic PDF issue that began with the Soft Harbor discovery and expanded to 13 tracked PDFs across 5 bug fixes and 13+ commits. Every single PDF in the Quiet Rooms collection now verifies with MediaBox 576×720 pt (true 8×10). The fix that required a cache-busting query parameter at 11:39 AM is now accessible via the plain…