It's messy at the moment.
http://www.dji.com/flysafe/geo-system/unlock 
They are using this one for geofencing, but there are mixed messages about whether all the yellow areas will require daily self authorising when it's properly implemented.
The 2.5 app initially turned this on with no mention of the changes in the details.
Presumably it is still able to make changes without your consent.

The unlocking option is still in beta stage and it doesn't seem to work properly if you don't have cell data available and turned on at the flight location,
I guess DJI assume everywhere should has 3G cover now!