Time-dependent Fourier filling fraction normalized by the maximum Fourier filling of the 2022EHT array. The curves represent the filling fraction of the 2022EHT array, 2022EHT + AMT array and 2022EHT + Africa array, in blue, red and brown, respectively. The dashed gray line corresponds to the lower limit used for identifying good time windows to perform dynamical imaging. The optimal time regions for the current EHT array are shown in blue. The 2022EHT + AMT adds three time windows (red areas) of ~4h in total, while the 2022EHT + Africa array (brown area) produces a time window of ~7.4 h.