Enviroment Lighting from Sky not updating in realtime

I have a game which is going to have 3D procedurally generated terrain with a day night cycle. As a result, I can't really have any object marked as static because everything is created at run time and all the lights move. I understand this means that I can't have any Global Illumination at all, which I'm happy to sacrifice.

My problem however, is that I'd like to be able to have the sky as the ambient light source for the world. Unity 5's new lightmapping panel seems to offer this option under the Environment Lighting section, but it doesn't appear to dynamically update the environment lighting if I change the time of day (With continuous build unchecked of course, since I can't build lightmaps when the game is running).

My understanding from the way the environment lighting is done (since it's just a special ambient light that has different intensities depending on your surface normal), this should be possible to do in realtime no sweat.

But even though I feel I've fiddled with all the settings, I still can't make the environment lighting from the skybox update in realtime, even though the skybox itself is updating just fine.

Does anyone know how I might solve this problem?