Below is the relative positioning and routes of the main protests. Around 11:45pm-12am, the police are most likely to use force and chemical weapons in order to get protesters to leave downtown. This could be seen as an unspoken curfew to clear out the area for the night.
Seattle positioning below:The Snapchat Map has a heatmap that is very good at being utilized as a realtime heatmap for protests/riots as it is happening. Example below: