Spline nodes can't be rotated along X-axis

When working with the Camera Rig Rail, the mesh representing the spline (rail mesh) doesn’t seem to rotate along the X-axis when rotating the node. Is this just a visualization issue or is the spline node locked in the X-axis for some reason?

Solution here: https://answers.unrealengine.com/questions/862387/completely-rotate-spline-points-including-roll.html#comment-880054-form