After a break I returned to UE4, and saw, that I needed to rebuild the lighting.
I just upgraded to 4.9 shootergame.
The build is fine, but it gives errors at the end.
Warning Hill Instanced meshes don’t yet support unique static lighting for each LOD, lighting on LOD 1+ may be incorrect
It only happens for my landscapes, and it writes the error many times foreach landscape I have.
I can’t find anything to fix it, and rebuilding doesn’t work.
P.S I haven’t changed the landscape since 4.8.