Not knowing much about how they're delivered through the continuum, nurses, particularly practical nurses, the greater majority of whom work casual or part-time, many times will get their shifts 24 hours in advance. You may not know from a tour of duty, which is about two weeks long from tour to tour, whether you're going to have work or not. Speaking from a personal perspective, you can't very well register your child in a full-time day care not knowing if you're going to have day care or if you're going to have shifts to pay for the day care.
On May 8th, 2007. See this statement in context.