This revised version (v2) of UCM Paper 10 formally withdraws the laboratory experiment proposed in the original submission (v1, April 2026). The UV-laser photoelectric-asymmetry experiment based on substrate rest-frame coupling cannot be sustained: the proposed coefficient cTZ (E) = (vₑff/c) (E/E_Λ) ² extrapolates to order unity at E ≈ 1 keV and exceeds SME bounds on electron-sector Lorentz violation by 25 to 40 orders of magnitude at Penning-trap, LEP, Compton-edge, and cosmic-ray energies. The scale-selection problem (why the coupling would use E_Λ = 23. 9 eV rather than the Planck scale) was already declared as the highest-priority open problem in v1; in the absence of a derived saturation mechanism, the prediction cannot be defended. The UV-laser experiment is therefore withdrawn. The remainder of the U-Cell Model is not affected. In particular, the Wilson RG attractor delivering emergent Lorentz symmetry (Paper 26), the dark-matter sub-threshold mechanism with 23. 9 eV as a Lorentz scalar of the substrate dispersion (Part D), the cosmological predictions Ω_Λ = 0. 6834 and w = -1 with cumulative ΔBIC = +27. 1 across twelve probes (Paper 51 and the observational suite), the Bell-correlation mechanism (Paper 31), the electroweak derivation (Papers 49-51), and the well-defined lattice path integral (Paper 54) remain in force. The paper specifies the empirical falsification conditions that continue to apply: significant deviation from w = -1 in DESI/Euclid/LSST, from Ω_Λ = 0. 6834 in post-Planck CMB analyses, loss of fcold universality in extended SPARC-like samples, deviation from g† = fcold⁴·cH₀, or refutation of sin²θW = 3/8 at unification. Revising an experimental prediction openly is less comfortable than letting it stand. Publishing this correction is the minimum owed to any reader who may have planned laboratory follow-up on the basis of v1.
Norbert Prebeck (Sun,) studied this question.