Not sure I fully understand but will take a shot: a project has a Task A, Kurt is assigned to it and the task also has an approval on it in which Kurt is the approver. The next project Task A approval now has Sean on it so Task A also needs to be assigned to Sean...I think I got it. Unless you have Fusion there isn't an automatic way to do this in the system, it is a manual effort to assign your task and/or mirror that person to the approval of the task (vice versa its still manual effort).