Moving files within LR creates duplicates then fails

I've seen this issue about 5 times now. It seems to have started recently and perhaps around the time I started seeing import duplication. 

REPRO (not consistent)

1. select a range of images within a folder inside LR
2. in LIBRARY, find folder tree for the drive you want to work with and right click on folder you want to create a child within
3. create child folder - checkmark "incllude selected photos"
4. LR starts to move the files but throws error. Complains about files already being at the destination but the destination was just generated at time of move. 

Now I have files in new location and duplicates in the old location.