Navigation (and rerouting) with “Next waypoint” is not strict, can still exit and resume route anywhere skipping intermediate waypoints automatically.
Cannot do that with “Strict navigation”:
“Navigate along the route without shortcuts, i.e. follow the route strictly from one waypoint to another. When go off route, the rerouting tries to resume to the last omitted waypoint.”
“Unvisited” was a false term based on the above description.
Shaping points are considered after next waypoint, like discussed here for all rerouting modes.