Illustration of how we combine groups of time-delay estimates in a series on the ECAM data set for the lensed quasar SDSS J1226−0006. Left panel: series of time-delay estimates obtained for the free-knot spline technique. Each time-delay estimate presented on the plot corresponds to a particular choice of estimator parameters for the mean spacing between the knots of the intrinsic spline η, and of the extrinsic splines η_ml. The combined estimate is shown both in black at the bottom of the panel and in a grey shaded band, to visually ease the comparison with individual estimates and it corresponds to the combination described in Sect. 3.3 with τ_thresh = 0.5. The estimates used to produce this combination are marked with ^*. Right panel: series of time-delay estimates obtained with the regression difference technique. The sets of parameter are detailed in Table 2.