I just going to give my two cents 
.
I’m too experiencing the issue, and I’ve notice the issue after I updated to the final release of DT3, while in the betas I didn’t notice. I don’t know if the progress bar was showing up in during the betas, but It’s the first time happened.
I’ve also had problems with my sync in general after I’ve updated to the final release.
In addiction I also have problems sending mails from iCloud email yesterday.
I really think that all of this is just an accumulation of coincidences related to iCloud and perhaps something has changed in the final and golden master releases of DT3.
Let’s see if the new release and time is able to fix all the issues.
PS/ I really think DT3 is involved, on one way or another.