The issue hasn’t stopped, sadly. And I’ve just tried setting up an entirely new scene, using the same assets, but instead of Directional lights this time, I tried Rect lights. The problem still happens with the Lighting Channels. 
The issue hasn’t stopped, sadly. And I’ve just tried setting up an entirely new scene, using the same assets, but instead of Directional lights this time, I tried Rect lights. The problem still happens with the Lighting Channels.