HST18 BeAR posteriors with a fixed surface gravity of log 𝑔 = 4.268 ± 0.006 and vertically uniform (left column) versus non-uniform (right column) H₂O abundances as a sequence over all 6 orbits in 2018. Each orbit consist of 11 intra-orbit spectra. Orbit-averaged posteriors are shown in red. The reduced chi-square values correspond to a fit of a straight line through all posteriors of a given parameter. The lowest panel represents the brightness change in G141 broad band, normalized by 3.0 × 10⁻¹³ erg/s/cm²/µm (data taken from Bowler et al. 2020 and Zhou et al. 2022).