The climb to 40,000+ feet points to two things, and two things only; either to kill the passengers or extinguish a fire.. ACARS could’ve been turned off without ever having to turn the knob off.. It could’ve happened electrically due to fire. If the wires are compromised it doesn’t matter what position the switches or knobs are in. The electrical system could’ve also gone haywire and communications cut right after the ‘alright, good night’ message.
“The climb to 40,000+ feet points to two things, and two things only; either to kill the passengers or extinguish a fire”
If there is a fire, you do not climb. If anything, you don oxygen masks and make an emergency descent, looking for the nearest suitable airport.
If 35,000 feet doesn’t do it neither will 40,000. That doesn’t wash.