Starting structures within each Voronoi cell were generated from a SMD simulation, where the system was started from a bound state configuration and pulled out to a site-ligand from a distance of 1 Å to a distance of 13 Å over the course of 20 ns of constant volume (NVT) MD using a moving harmonic restraint with a spring constant of 9000 kJ•mol -1 •nm -2 . Upon examination, we determined that the original 14 Å milestones showed anomalous results in the BD, probably due to solvation shell effects and steric hindrances caused by the rigid body approach in BD. We added milestones beyond the original 14 Å to improve the calculation by moving the BD region beyond the solvation shells. Starting structures beyond the 14 Å milestone were extracted sequentially from the states generated at the moments of MMVT collisions against lower milestones. Using the generated starting structures for each Voronoi cell, a total of 500 ns of MMVT MD simulations per cell were performed using SEEKR2. All collisions against the milestones were recorded for later analysis. For the BD simulations, the ligand was started at the b-surface and proceeded until it either escaped or satisfied the "reaction criteria" of touching the 18 Å radius milestone (b-surface stage). Then, among those that touched the 18 Å milestone, 1000 structures were extracted, and from each of these, 1000 independent BD simulations were run until the ligands either escaped or touched the 16 Å milestone (BD milestone stage). The purpose of the b-surface stage is to compute the rate of initial encounter with the outermost *15 milestone, while the BD milestone stage computes transition probabilities used in the milestoning model which are used, in combination with the initial encounter rate, to compute the kon.