K₁ semi-amplitude vs. period diagram of SB1 solutions, colour coded according to their astrometric_excess_noise. The diagram shows the presence of an overdensity of solutions at periods near the precession period (marked with a vertical line) with large astrometric excess noise. The histogram at the top shows the density of solutions with astrometric excess noise larger than 1 mas (blue line) and of those with ipd_frac_multi_peak > 20 (orange line).