Comparison between the PLZ coefficients obtained for different global offset values. The coefficient values obtained without offset assumption are chosen as reference and are on the x-axis, while those obtained whilst assuming the global parallax offset by Riess et al. (2021) and Molinaro et al. (2023) are on the y-axis and are plotted with green and pink symbols, respectively. From top-left to bottom-right, the panels show the results for the α, β, γ, and δ coefficients, respectively. For each coefficient, different photometric bands are plotted using different symbols, as labelled in the top-left panel, while grey-filled and white-filled symbols indicate the fit results including or excluding the δ parameter, respectively.