Mean transmission, ⟨T⟩, over 1215 − 1230 Å rest-frame for each galaxy in our sample (grey circles), as a function of spectroscopic redshift, including only sources with redshifts from emission lines. ⟨T⟩ corresponds to the flux around the Lyα break relative to the predicted galaxy continuum in an ionized IGM, with no contribution from Lyα emission or absorption by HI. Thus ⟨T⟩> 1 corresponds to Lyα emission, and ⟨T⟩< 1 to absorption. We show the median and 68% range of ⟨T⟩ in four redshift bins (coloured circles). The blue line and shaded regions shows the predicted median and 68% range of ⟨T⟩ assuming the z ≲ 6 template spectra described in Section 5.1 and the reionisation history inferred by Mason et al. (2019). The observed median and range are in close agreement with the IGM prediction.