Model stops animating when setting the clock backwards

[lilleyse]

It's possible that I'm doing something wrong here. Here's a code snippet.

var viewer = new Cesium.Viewer('cesiumContainer', {
    infoBox : false,
    selectionIndicator : false
});

var cesiumAirEntity = viewer.entities.add({
    position : Cesium.Cartesian3.fromRadians(-1.31968, 0.698874, 100.0),
    name : 'Cesium Air',
    height : 20.0,
    model : {
        uri : '../../SampleData/models/CesiumAir/Cesium_Air.glb'
    }
});

viewer.trackedEntity = cesiumAirEntity;

viewer.clock.currentTime = new Cesium.JulianDate(2457522.154792);

// Set time backwards after 2 seconds. Setting time forward works.
window.setTimeout(function() {
    viewer.clock.currentTime = new Cesium.JulianDate(2457422.154792);
}, 2000);