The percentage makespan gap between the baseline and the MILP schedule, defined as percentage makespan gap = e baseline max -e MILP max e baseline max is used to evaluate the MILP scheduler. Figure shows the percentage makespan gap distributions between the baseline schedule and the optimal MILP schedule for all libraries grouped by the number of target chemicals (the groups are listed in Section S3). Note only optimal schedules are included in Figure and not all scheduling instances converged to an optimal solution due to the 3-hour scheduler time limit (Section 2.5), as a result, several library groups have fewer than ten percentage gap values shown in Figure ; the full set of results including suboptimal MILP schedules can be found in the project repository. The makespan of the optimal MILP schedule tends to be shorter than that of baseline schedule, with a few exceptions for very small libraries (number of targets ≤ 2) where the gap is negligible. This is not surprising as the solution space of small libraries is also small.