We appreciate everyone's patience while the team worked on providing us a fix. As most of you have noticed, S8/S8+ users who are having this issue should be and will be notified by Galaxy Apps for an upgrade (over the air) to address the issue.
I had luck doing this:
1. Go to the App Manager under settings
2. Use the drop-down menu in the top right to enable "Show System Apps"
3. Find DQA from the app list
4. Select "Data Usage"
5. Disable "Allow background data usage"
Since I don't know what DQA is, I wouldn't call this a long-term solution, but it should hold until Samsung can issue a fix/patch. Let me know if this helped, it worked for me! I saw other people on other boards suggest doing a system catch from Recovery mode, but that didn't do it for me, nor did restarting my phone several times.
Got the same issue after the update. It seems related to wifi. I don't get the message when i wifi off. Dqa stands for data quality assessment, so it seems to be a bhug in this update that affects wifi.it also slows down connection.