iPhone data usage System Services Time and Location
Ever since last month, the data use under System Services -> Time and Location has increased "dramatically". It's pretty consistently half of my data use, whatever I do. I haven't added any new apps or use the phone differently than I have in previous months.
I use one tracking app, Human, but even if I turn mobile data off for it, data use under Time and Location continues to be half of my mobile data.
How do I start trouble shooting? I've read threads here and deactivated mobile data and background updating and syncing for most things. This has decreased data use, of course, but time and location still continues to be half of my data.
I'm on a 1GB plan, which used to be plenty, now I get close to maxxing it out when I'm not careful.
iPhone 6s, iOS 9.3.2