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Alright so I’m pretty sure I just got bit by this.

I just started using a VPN while at work to keep my company from sniffing my WiFi traffic. Well yesterday I got an alert saying that I almost used used up all my data for the month. When I look at my cell account and compare the data usage to what my iPhone says, it perfectly lines up with what my VPN app is reported to have used.

I turn on my VPN while still in the parking lot so what I think is happening is traffic flowing through the VPN before I get in the building gets pinned to cellular data all day while I’m at work and doesn’t actually us my WiFi.
 
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