For me that only happens while using time preview. Once you select the time and let it load its normal. Not really a big deal.
In that case, it's entirely normal, since lots of our sceneries are created programmatically, including loading different version of the object for day or night, which saves VRAM compared to standard methods ( at dusk/dawn both night and day textures are loaded together, but not if we can control the object creation and draw a completely different one in that case ), but during Time Preview, the simulator Time doesn't really change until is applied, so our code doesn't know if it's night or day until you Apply the time.
