The arXiv preprint (v1, June 2026) reports JWST/NIRSpec prism spectroscopy of a single quasar, UDS-27023 at z=4.556, whose far-UV extinction curve reaches A_1500/A_V ≈ 8 while lacking the 2175 Å bump. This steep, featureless curve is interpreted as dominance of sub-0.1 μm silicate grains produced or processed by AGN-driven shocks and winds. Methodology rests on template subtraction against composite QSO spectra rather than full SED modeling; with N=1 the result is necessarily anecdotal. Preprint status means it has not yet undergone peer review. The finding directly challenges the canonical two-step dust timeline in which core-collapse supernovae first supply large grains that later grow via accretion; instead it implies a rapid small-grain channel that can boost ISM surface area and accelerate enrichment within <500 Myr. Earlier ALMA surveys of z>6 dusty galaxies (e.g., the 2022 Nature Astronomy sample of 18 sources by Witstok et al.) already hinted at unexpectedly high dust masses, yet lacked the UV spectral resolution to distinguish grain-size distributions. The new SEQ population may therefore represent the missing “processing phase” that links supernova ejecta to the massive reservoirs seen in luminous high-z systems. Limitations include possible line-of-sight geometry effects and the absence of mid-IR constraints that could confirm or refute in-situ condensation in outflows.