How staging is generated and calculated
As teeth move, stages are automatically added based on the amount of movement made. The amount of movement per stage gets determined by Stage Parameters, which is adjustable in Settings.
You can adjust separated upper and lower staging in Settings. When Separate Upper/Lower is selected, the software only generates the minimum required number of stages for each arch.

To visually move through the stages, click and drag along the timeline.
The Initial stage is the model with attachments but no movements. This attachment template is used for bonding attachments.