WoL for Telit GE864 / General M2M tips?

I cannot fathom how this would be possible, but I figured there might be some knowledge here on how to best deal with this situation.

I’m running some mobile devices with a Telit GE864. They are running from a battery, so they turn off when not in use. These devices send sensor data, but also have relay control built in. Is there any equivalent to ‘Wake-on-LAN’ for M2M modules? I don’t know how you would address a disconnected node, but…

Alternatively, I guess I can connect to a server every ~6 hours and see if there’s a new command waiting, but anything realtime goes out the window.

Thanks for any and all thoughts!