Force LODS unloading

Can I force a Lod to unload under a certain minSize? I have a scenery with
very long objects (200 to 500 meters, but can be also 1000 meters). Those
objects are cables hanging from Power pylons The engine keeps the objects
“Active” until It reaches 0.5 % size. But for this kind of objects i find ok
to unload them at 20 or 30% size, because they are so tiny that won’t be
visible even at that size My last lod Is already optimized (6 vertex and no
material) , but i can’t find any reason to keep invisible objects into memory
(Pretty specific question yeah)