This is the 3rd time I find my base with no ore, and I go diagnose and I find a random detached rouge wagon from the train... with no explanation, no idea what happaned, and wasn't there to see. I'm deep into late game, but this has happaned several times. I use L-C-C trains in my Nauvis system, and this is just bizzare.
Here are some screenshots of when it happens:


As you can see super weird, and no idea... So I guess it's a bug?
Thanks!