Schedule reserves are the amount of time allocated for unforeseen risks or delays in a project. They are usually calculated based on the level of uncertainty and complexity of the project. In a hybrid project, where both agile and predictive approaches are used, the project manager should reconsider the necessary schedule reserves based on the progress and performance of each module. By doing so, the project manager can identify the critical path, prioritize the work, and adjust the schedule accordingly. This can help to take the schedule back and accelerate the ROI of the project. References: PMBOK Guide 7th Edition, Chapter 8.3.3.2; Agile Practice Guide, Section 3.2.2.