Role of eccentricity in a mock binary in the best-case observing scenario. Corner plots show Δm₂ and v_k posteriors in the best-case observing scenario (SOV₃, see Sect. 3.1). In panel a, we correctly assume a circular prior for the initially circular mock system, whereas in panel b we used the eccentric prior for the initially circular system. In panel c, we use a circular prior for the initially eccentric mock system, to test the impact of prior misspecification. The gray shaded regions and quoted intervals indicate the 90% CI for the 1D distributions, while black contours indicate the 90% CI for the two parameter correlated distributions. Black, dashed lines show the true values. (a) Circular binary with circular prior. (b) Circular binary with eccentric prior. (c) Eccentric binary with circular prior.