I was sure I saw this error reported in the forums but I cant find it now, the symptoms are that bluetooth, once turned off, cannot be re-enabled without rebooting. In my situation this seems to be caused by the Pebble watch app.
If I reboot with bluetooth on the pebble app connects to my pebble. If I then use the system settings to turn off bluetooth i cannot start it again, the BT on slider moves to the on position then immediately slides back to off. I have found no way to fix this short of rebooting.
If I do the same boot but this time either kill the pebble app, or use the pebble app to disconnect the pebble then I can freely turn BT on and off.