Derived by the Research Lead from Guang Zhang's paper: test Strategy C, which enters a hedged pair when a filtered spread returns inside its trading boundaries and exits at equilibrium or renewed divergence. Use PEP and KO daily bars on USEQ, retaining the paper's empirical Model II: linear mean-reverting drift with state-dependent Gaussian innovation variance. This is a distilled implementation, not a reproduction of the reported returns. Research Lead additions are a causal 756-session estimation window, explicitly defined volatility-dependent boundaries, equity-relative sizing and protective exits. Replace the paper's simulation-selected boundaries with the platform's training-only, net-of-cost walk-forward selection; do not introduce a second simulation-based parameter search. Execute market orders after both completed daily bars arrive, at the modeled session close. No next-session-open execution is required. Fit model coefficients using only the pre-evaluation training window, then freeze them throughout each evaluation segment. Deployment freezes coefficients and trading parameters. USEQ prices are split-adjusted rather than dividend-adjusted, so this tests price convergence and does not reproduce the paper's adjusted-price economics.