react-native-fs: Cannot access SDcard (ExternalStorageDirectoryPath points to /storage/emulated/0)

Hello, I am trying to access and modify files on an external SDcard on Android Marshmallow 6.0.1 (SDK 22) In AndroidManifest.xml I have declared following permissions:

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

When I print RNFS.ExternalStorageDirectoryPath I can only get an emulated path (/storage/emulated/0) which is not on the SDcard.

I think this is most likely some permissions issue but I have checked everything: app permissions in settings which have storage enabled and also when I check the storage permissions dynamically using this code

    const granted = await PermissionsAndroid.request(
        PermissionsAndroid.PERMISSIONS.WRITE_EXTERNAL_STORAGE, {
            title: "Grant SD card access",
            message: "We need access"
        }
    );
    if (granted === PermissionsAndroid.RESULTS.GRANTED) {
        console.warn("Permission OK");
    }

It works as expected so I am really out of ideas. Is there anything I might be missing or is this a bug with the library? Thank you for any help with this.