HST white light curves for the three transits, shifted to their individual mid-transit times and shown in hours. Blue transits correspond to those taken with the G430L grating, and red to the one collected with the G750L grating. Left: from top to bottom we show the transit light curves with the systematic effects, along with our best-fit combined model (transit times detrending), the detrended data along with our best-fit transit model, and the residual light curves after both components were subtracted. Right: zoom in to the residuals. Dashed horizontal lines indicate ±1 and ±3 times the standard deviation of the residuals to guide the eyes.