Same as Fig. 3 but for different fixed parameters, i.e., the oblateness, C_20, 1, and the tidal time lag, Δt₁. For the second component we assumed the same values. The uncertainties of ETVs were revised to 10⁻⁴ d. We tested 121 pairs of parameters, 300, 300, and 1000 sequential iterations of simplex: 1.9 × 10⁵ models in total. The parameters of the inner Aa+Ab orbit (plus P₂) were free. The best fit is indicated (red) along with a statistically equivalent, close-to-zero C_20, 1 solution (green). Zero Δt₁ is excluded.