ALMA-APEX-PV (top) closure phases of M87* as observed in 2017, 2018 and 2021. The ALMA-PV-NOEMA (middle) and ALMA-SMT-KP (bottom) closure phases on M87* observed on April 18, 2021 (figure is adapted from EHTC 2025) are shown together with ring-image models obtained with different imaging algorithms (see text for details). The top panel shows an example of a trivial closure phase triangle, where two stations are co-located, see Georgiev et al. (2025) for details. The image models are discrepant with the observed data by a few degrees, which may be attributable to intermediate-scale emission observed on the PV-NOEMA and SMT-KP baselines.