Luminosity distance and chirp mass for a well-localised, eclipsing and chirping UCB. The 12-month posteriors f and A the binary from Fig. 2 were re-sampled using Eq. (2) to form the luminosity distance D_L and chirp mass M_⊙ posteriors. The black marker on the graph corresponds to the D_L and M_c derived by substituting the injected LDC parameters into Eq. (2). See Fig. 2 for a description of the three colours.