Posterior distributions of the key dynamical parameters near the 2:1 MMR for the two-planet system, derived from a combined TTV + RV N-body model. A total of 10,000 samples were drawn from the posterior distribution and individually tested for long-term stability. The distributions reflect the system’s behavior in the vicinity of the 2:1 period ratio, highlighting the resonant and secular dynamics. We report the median values and peak-to-peak variations of the period ratio (﹩{\hat{P}}_{{\rm{rat.}}}﹩), eccentricities (﹩{\hat{e}}_{{\rm{b}}}﹩, ﹩{\hat{e}}_{{\rm{c}}}﹩), and apsidal angle difference (﹩\hat{{\rm{\Delta }}\omega }﹩), along with their dynamical amplitudes: Ampl. e_b, Ampl. e_c, and Ampl. Δω. Dynamically constrained planetary masses and semimajor axes are also shown. The resonant angles θ₁ and θ₂ are omitted as their evolution is dominated by circulation over the full 0°–360° range. Contours in the 2D distributions indicate the 1σ, 2σ, and 3σ confidence intervals of the stable posterior set.