Each section has a pickup measure and an overhang measure. This makes it possible to record notes into a section even if they occur before the downbeat of bar 1, or after what would normally be considered the last bar of the section. The pickup and overhang measures are part of the section: they go with the section wherever the section goes. But the best part is that they don’t get in the way. For example, when you work with sections in a song, a four bar section is still a four bar section, even if it has a few pickup notes.