Well you beat me to the post. I was waiting for a few days to see if it stopped but it hasn't.
It just isn't a popup it's a full page thing. Have to click "continue to site or the X on the right side. Pain in the ass actually and don't understand why when you are logged in you have to get this as a subscriber. I already received an email on the same thing. So I understand not everyone is getting this but I only asked one other person. Don't know how long you have been receiving it but it's about 4 days for me.
Really hope someone gives us a good reason for this.