Corner plots of the distribution of fitted values in position (α, δ) and contrast c for an off-axis companion located at α = +5.0 mas, δ = +5.0 mas and with a contrast c = 10⁻³. The figures show the distributions of the respective parameters with varying piston residual size. Left panel: at 50 nm, we see well-distributed values around the coordinate locations of the companion with σ_RA = 0.22 mas and σ_Dec = 0.25 mas. Middle panel: at 100 nm, we begin to see some flux leakage from the null particularly in the δ distribution with σ_RA = 2.01 mas and σ_Dec = 2.26 mas. Right panel: at 150 nm, the piston-induced leaked intensity is more pronounced for both α and δ with σ_RA = 4.11 mas and σ_Dec = 4.30 mas. Each four-UT MC simulated data-set consists of 10⁴ series of kernel outputs acquired in the presence of a controlled amount of residual phase noise.