Hello there 
When unloading a Streaming Level using Blueprints on a Client’s machine, some of the Light of the unloaded level still affects the newly loaded level.
All my lights are moveable.
Here is a video showcasing the bug.
I also posted the question on the Blueprint forum but I figured it might just be a rendering bug so I’m posting here too. You can find additional information on this thread.
I did not tried to recreate the bug in a clean project because I apparently had no problem with a less complex light setup.
Thanks in advance for any lead or answer