Total intensity closure phase evolution of M87^* synthetic data from example MAD (M) and SANE (S) standard models as a function of model variability for the ALMA-LMT-SMT and LMT-PV-SMT triangles, respectively. Spin a_* = s and R_high = r parameters are listed in a shorthand notation as a_s and R_r in the legend of the bottom panel. Each data point corresponds to a VLBI scan-averaged synthetic data closure phase measured at 02:27 UT on 11 April 2017 and the standard deviations plotted are computed from multiple synthetic data realizations of the same model frame. The corresponding measurement range from the 2017 observational data is depicted with a gray band. The SANE model shown here has been ray-traced for 600 frames only.