What does UD 1 means?

Does anyone else sees UD 1 in their profile after upgrade to 11 from 10.5? What does it means?

I asked this question too but no one replied. Maybe it stands for update. Anyway, it seems to disappear after activation.

Yes it disappeared here too. I think they needed to do something with the activation problems, so whatever they did, it is a side effect of it. I guess they are fixing it behind scenes.