Early (up to 20 Myr) evolution of the total mass, M_BH, bound (top left), and number, N_BH, bound (bottom left) of the BHs bound within the M_cl(0) = 5.0 × 10⁴ M_⊙ (initially all single stars) model cluster (see Sect. 3) for the various remnant-formation schemes (legend), for the standard, fallback-controlled kick model as given by Eq. (1) (Z = 0.0001 is assumed). The corresponding evolutions of the half-mass radius of the cluster’s BH subsystem, r_{h, BH, bound} (top right), and that of only the luminous members, r_h, * (bottom right), are also shown.