Per the design note (variant a, "EMA on (α_t, β_t)"): each team's attack/defence parameters should EVOLVE through time rather than absorb every era's matches into a single stationary compromise. Refit DC at K snapshot timestamps (= the 8 quarterly walk cutoffs), blend each team's parameters across snapshots via an exponential moving average with tunable half-life h_param, and check whether the blended parameter trajectory beats the stationary baseline on walk-forward Brier / ECE.
Reasoning: