I have seen some similar topics on whehter BUE will automatically reclaim expired Media sets on a NAS device, or basically any B2D folder which cannot have a Windows Agent installed.
I have setups, where it does delete the sets's and other clients where it cannot. I read that this can be erratic.
My only option would be to set a reminder to manually expire/delete the media
Anyone with simlilar situation
set up is Daily job to RDX which works as expected
There is a Monthly job to NAS which seems to be problematic