Milestones are in place to allow a character to advance by role-playing and/or taking part in the story. A Milestone is considered “completed” when a character reaches the 10xp milestone.
Characters may only swap out Milestones once one has been completed or one may be swapped out between Acts. Milestone limits are as follows:
1xp milestone may be reached one time every Scene.
3xp milestone may be reached once per episode.
10xp milestone may be reached once per Act.
Note that a starting character starts with two milestones. The above rules are per Milestone. For example:
You may reach the 1xp milestone from your Story Milestone and/or Character Milestone in the same Scene for a total of two xp for that Scene.