Despite its title, the Office of Personnel Management’s new “Handbook on Leave and Workplace Flexibilities for Childbirth, Adoption, and Foster Care” is also a helpful resource for childless feds. But this handbook doesn’t tell you everything you need to know about maximizing leave time and avoiding sacrificing leave due you. Some highlights on this topic: If you’ve been preapproved to take leave on a day that ends up being a snow day, you will be charged for that leave anyway. So, if you’re planning to take leave on a day that may overlap with a snow day, consider delaying your…