RV data phase-folded to the period P and central time of transit t0 (shown above each panel, t₀ units are BJD – 2 457 000) derived from the joint-fit model. Here, we show APF (blue circles), HIRES (green up triangles), CARMENES (red squares), and HARPS-N (orange down triangles) RVs phase-folded for HD 191939 b (panel a), c (panel b), d (panel c), e (panel d), and g (panel e) along with the best-fit model (black line) and the 3σ confidence interval (shaded grey area). The error bars include the instrumental jitter term added in quadrature.