GarageYears... Thanks for that article. Makes sense that the protocol to keep the satellite link subscribed is in the satellite transceiver itself so it will ping as long as it has power, even without incoming data.
Hopefully someone is looking into how ARINC 629 cables failing could make it appear that ACARS and Transponders were turned off by a human. Failure of that buss would also mean that the VHF and HF control heads (as well as others) on the flight deck could not connect to their LRUs. Even a short duration fire could cause a real mess in a hurry.