If a device has to get added again, it is treated as a new device. If you had Rules or Scenes set up you could add the new one in but settings specific to the old one (even if it is really the same device) are lost.
I have read about this happening for other people's light bulbs on the forum. Sometimes traced to it being a light switch someone flipped a bunch of times (resetting it) sometimes with no idea why it happened. But it has been the bulb typically. None of my GE Wink bulbs have done this but I do know other people have seen it on those. Not sure about OSRAM though, I cannot remember reading about one prior to yours.