By now, you should know the following about your cast. You should know the threat posed to them, and most importantly, have a strong sense of the stakes driving each member. You've also developed some visual and sensory tags to make cast members distinct from one another. If more than one cast member serves as a viewpoint character, their perspectives are diverse and make the world more interesting through their unique narrative voice. At this point, some people sit down and plot out their story, scene by scene, while others tell their story through action and reaction.
Pinning points are a loose plotting technique that is goal-oriented.
For instance, if one of the characters has a history of alcoholism and this detail bears on the story, then we find a place in the story where this information can be revealed to best effect. You should have at least one pinning point for each cast member. Actually, the more important a character is to the story, the more dots in their character arc there should be. As in most good movies, there is a time when each character will get a chance on center stage. This is your best opportunity to reveal whatever hidden truth or secret this character may be concealing.