We coordinated meetings this month so we could practice all our parts together. We tried to split up parts based on each member's strengths and preferences, though the Project Manager, Alice Wu, decided that everyone had to practice every part of the presentation so splitting would be easier, and also in case someone didn't show up for one of his/her assigned presentations. Then there would be three other people who could take over the part, leaving the presentation still intact and flowing.
However, we also practiced for presentations in presentation groups, coordinating the groups so absences will have minimal impacts on the presentations' quality and effectiveness. At the same time, any surprise absences shouldn't affect the presentations too much since everyone knows all parts of the speech and information to include.