You can try to setup an Event Rule which sends back a reset command to the device if you have no valid position for a specific time.
Do like this:
A. Create a Template Command which resets the device. More info on Template Commands here:
Note that you can send the command over SMS. Or if the device supports GPRS commands, you can setup the command to be sent once the device connects / is connected.
The Terminal is a very useful tool when testing commands.
B. Create an Event Rule with an "Offline Expression" in Step 4. Set a time out, select rule to turn True of there is no "valid position".
Note that you can set the rule to only function during office hours (Step 2.).
C. Add a "Command Notifier" in Step 5. set it to send "back to device". Select your Template Command.
Now save and test!