The QDL–SO10–1 grand-unification sequence defines a closure-first SO (10) -compatible benchmark within the Quantized Dimensional Ledger (QDL) program. Papers #1–#3 established the initial benchmark trilogy: a fixed SO (10) -compatible benchmark, its low-energy phenomenology, and a stress-test / robustness audit. Paper #5 began the executable hardening sequence by revising the gauge-closure target to inverse alphaU = 44. 501718, corresponding to alphaU = 0. 022471. Paper #6 supplied a reduced block-level scalar-threshold derivation of the calibrated high-scale offsets, and Paper #7 converted proton decay from a scaling-level estimate into a benchmark-level operator exposure calculation with Wilson coefficients, hadronic inputs, channel-level lifetimes, and a reproducible v0. 4 artifact. This paper supplies the v0. 5 flavor and leptogenesis hardening layer. Its purpose is not to claim a final global SO (10) flavor scan or a unique microscopic flavor theory. Its purpose is to determine whether the QDL–SO10–1 benchmark is flavor-incoherent, or whether it can support a reduced SO (10) -compatible flavor ansatz that reproduces charged-fermion hierarchy, CKM mixing, type-I seesaw neutrino closure, PMNS mixing, neutrinoless-double-beta observables, baryogenesis viability, and proton-decay flavor feedback at benchmark level. The result uses a reduced H/F/G SO (10) -inspired texture at benchmark tolerance, not a complete global flavor scan. The v0. 5 executable artifact produces charged hierarchy ratios mᵤ: mc: mₜ approximately 10^-5: 3. 5 x 10^-3: 1, md: mₛ: mb approximately 1. 1 x 10^-3: 2. 1 x 10^-2: 1, and mₑ: mₘu: mₜau approximately 2. 9 x 10^-4: 5. 9 x 10^-2: 1. The CKM benchmark magnitudes are |Vᵤs| = 0. 224998, |Vcb| = 0. 041000, and |Vᵤb| = 0. 003700. The light-neutrino spectrum is normal ordered, with m₁ = 0. 0025 eV, m₂ = 0. 0090 eV, m₃ = 0. 0502 eV, Delta m₂1² = 7. 475 x 10^-5 eV², and Delta m₃1² = 2. 51379 x 10^-3 eV². The PMNS benchmark angles are sin² theta₁2 = 0. 304, sin² theta₂3 = 0. 573, and sin² theta₁3 = 0. 0222. The derived neutrino observables are sum mₙu = 0. 0617 eV, mbetabeta = 5. 44 meV, and mbeta = 9. 18 meV. A Davidson-Ibarra-style benchmark leptogenesis estimate gives epsilon₁ = 2. 3844 x 10^-6 with central washout efficiency kappaf = 0. 010, yielding etaB = 5. 57 x 10^-10, with the efficiency scan spanning 1. 67 x 10^-10 to 1. 67 x 10^-9. This is classified as viable benchmark leptogenesis, not a full Boltzmann-equation computation. Finally, the v0. 5 flavor factors are fed back into the proton-decay lifetimes of Paper #7. The updated lifetimes remain above present bounds: tau (p to e+ pi0) = 2. 396423 x 10³6 yr, tau (p to mu+ pi0) = 4. 088415 x 10³7 yr, tau (p to anti-nu K+) = 6. 459280 x 10³7 yr, tau (p to anti-nu pi+) = 7. 170619 x 10³6 yr, and tau (p to e+ K0) = 5. 885232 x 10³8 yr. Relative to Paper #7, the v0. 5 feedback shortens the p to anti-nu K+ lifetime by a factor of approximately 2. 25 while keeping it roughly 1. 1 x 10⁴ times above the Super-Kamiokande comparison limit used in the paper. Thus QDL–SO10–1 survives v0. 5 flavor and leptogenesis hardening at benchmark level. The result closes the last major open technical layer of the hardening sequence and makes the benchmark synthesis-ready for Paper #9. The v0. 5 standard is not arbitrary flavor fitting; it is flavor closure under QDL admissibility with leptogenesis and proton-decay feedback.
James D. Bourassa (Mon,) studied this question.