Make rough estimates, later fill in subcases. When planning for a given cycle, it may be difficult to break down all of the work into cases that are 3 - 5 hours in length. That's okay. Create a more generic case with a given estimate. When you get closer to actually working on it, then split it into smaller chunks. Each of these chucks should be a subcase, and you should shift time from the parent case for each of the subcases. (
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