Milestones were ten loose dates you pushed around one at a time. Now each one can carry a duration, follow another milestone with an optional lag, and the dates work themselves out: slip FAT and Ship, Materials on Site, and everything after move with it. A timeline above the table draws the plan as bars you can drag and resize, with week, month, and quarter views and a today line. An empty schedule can start from the standard sequence, Kickoff through Substantial Completion already chained with typical spacing, so the first draft takes one date and one click. Recording an actual date pins that milestone where it really landed, and the rest of the plan flows from it. Procurement's need-by dates and the Submittal Log's proposal hint read from the same schedule, so there is one plan, not three.
The schedule also works the way a schedule is used. Durations and lags count working days, so weekends stop hiding inside "10 days of fabrication". Every change that ripples shows an Undo, and a history keeps who moved what, when. The chain that decides the finish date gets a heavier outline, milestones that drive purchasing say so on their row, and dragging a bar shows the date it will land on. Dragging a dependent bar slides its lag behind its predecessor, so the whole chain stays honest. Project followers hear about it when one edit moves the finish date a week or more, and the whole timeline exports as a PDF Gantt or a spreadsheet.