Parametric Spitzer phase curves with error bars based on Eq. (1) and best-fit models from our 1.5D phase-curve retrieval. The dashed vertical lines indicate the position of the hot spot’s centre. Note: the orbital phase has been corrected for the light travel delay, so that mid-eclipse occurs at ϕ′ = 0.5. Left: chemistry is fixed at Z_p = 1 Z_⊙; Right: chemistry is fixed at Z_p = 10 Z_⊙.