The pipeline already loads its base_model VAE through VAELoader, so the existing h3_vae_nvfp4_decoder swap applies; this exposes it: a --h3-vae-nvfp4-decoder CLI flag, a --vae-decoder example flag, the serve option in the regen2k YAML, and the measured 2K decode/quality table in the guide. CPU tests pin the regen2k VAE load applying the exported decoder, the serve-config field reaching FastVideoArgs, and the new CLI flag.