Why am I seeing so many warning screens?

[Lemini 12]

I upgraded my account to Premium in June and from then until now I have used maybe 1GB or less of my upload limit per month. After realizing I had so much upload remaining and that the month was ending, I decided to add some of my technical books and textbooks to Evernote. In the process, I have uploaded around ~5GB of PDFs (and some audio files for my language textbooks).

Since hitting the 5GB mark not only have I noticed that syncing across my clients is now unbearably slow (I use the Mac and Windows desktop applications) but I have received an increasingly annoying series of notifications from Evernote. First, on the windows client I got two separate  pop-under notifications that remarked I used half of my allowance and prompted me to fill out a survey. After filling out the survey twice the pop-unders stopped.

I later checked my email and noticed the following message from Evernote:

   

I later on tried to clip an article with the web clipper and received the following notification:

 

Why am I receiving so many notifications and how can I opt-out? I'm well aware of how much of my limit I'm using so at this point all of these messages feel like harassment. I am especially unhappy with the notification I saw when clipping the web page. I feel like the notification is implying I'm abusing the service, simply for reaching half of my upload limit.