O-C diagrams (top and middle plot) for the solution K9-II in Table 6 from the fit of the T₀s for the 12 quarters and neglecting the six RV points. Colors and markers as in Fig. 12 for 56 d.o.f. In the bottom panel, the RV model (blue dots) from the solution K9-II with over plotted RV observations (black dots with error-bars). We do not have the RV residuals from TRADES, because we have not fitted the RVs. The RV model has a lower RV semi-amplitude of about 12.80 ms^-1 with respect to the RVs from the discovery paper.