Hello!
First of all, I’d like to address that I’m not an environment artist and this is just a learning project. That out of the way, I am having a slight lightning issue during my simple day night cycle which I cannot understand how to resolve.
When I first encountered the problem, I thought it was something to do with the Imposter Baker (GitHub - ictusbrucks/ImpostorBaker: UE4 Plugin for generating Impostors for static meshes) I am using. But after some debugging, I have noticed that it has nothing to do with my Imposter setup.
Here is a footage of my procedural trees that have Imposters/LODs setup:
Here is another footage of my procedural trees that do not have Imposters/LODs setup:
Under my Landscape lightning settings, I have “Shadow Two Sided” enabled which was used to fix the sun shining thru the landscape when it was below it:
My Foliage Type Object has these Instance settings (which I’ve tried playing around with but still couldn’t solve the problem):
The “General Settings” of the static tree mesh:
And finally, the material for the tree meshes (which is very simple):

From here, I don’t know where to look to fix this problem. If anyone could help me out and/or point me at the right direction, I’d greatly appreciate it.
Thanks!