AB comparisons in the g band. We show the overlapping periods between the light curves of A (filled circles) and B (open circles), where the fluxes of A are shifted by +417 d and are properly amplified (see main text). Top left panel: the overlap period for the first time segment of B, i.e., TS1 (days 4010–4249). The A signal is amplified by 1.086. Top right panel: the overlap period for TS2 (days 4498–4627). The A signal is amplified by 1.14. Bottom left panel: the overlap period for TS3 (days 4777–4992). The A signal is amplified by 1.086. Bottom right panel: the overlap period for TS4 (days 5107–5373). The A signal is amplified by 1.14.