T-Mobile Data Usage When On Home WiFi

Hola @w3wilkes Good on you for keeping an eye on your account and usage details. Does it seem like it is large amounts of data being recorded during the time that you are on your home wifi? There are a few things that I think could be happening. There is a slight delay in when the data is used and when it is timestamped. Since usage can be a continuous thing, the usage details are not tagged minute for minute so you will see chunks used minutes apart. Since you are home and sleeping, I don't assume this is the only cause, but a variable to consider. The data that registers on network could also be times when the phone is connected to wifi but still pinging the T-Mobile network for software updates, T-Mobile App diagnostics, and other things related directly to T-Mobile and your phone. These shouldn't be very large amounts of data, but can vary in size depending on what is happening. There may also be times when the wifi network might hiccup causing the phone to default to mobile data. These are just a few possibilities. 

Any data that you see on the usage details screen is considered mobile data and does add up to the monthly usage on your account. I am curious if there is a specific reason that you are worried about the data counting against your account. I like to make sure that all your concerns are addressed, so if you elaborate a bit, I would be happy to help any way that I can.