RST Engineering wrote:

It has been nearly fifty years since I went to Boeing school, so please
....
squat switches have to be enabled to restart the APU. It cannot be started
airborne.

I hardly believe that the Boeing school of 50 years ago covered Airbus
systems.

Besides, I'd assume that a plane entrely flown by wire must provide
features which guarantee controllability even in the event of a complete
engine failure to get certified in the first place.