Binary model fit (following the method described in RSR 24) of the residual O-C diagram of OGLE-LMC-CEP-2840 (also see Fig. 11). The black dashed line represents the orbital solution obtained from the median parameter values of the posterior distribution. The blue-shaded regions contain the ranges (credible intervals) of individual MCMC solutions according to one, two, and three standard deviation at a given point in time, in order of decreasing transparency. Above the panel the OGLE-ID, adopted pulsation period to construct the O − C diagram and the orbital period are shown.