Earlier quoted context omitted.
The problem isn’t the update itself, which is actually straightforward. It’s the fact that as soon as you modify the software you must do a c check on the craft. Which is a horribly long process, around 6,000 man-hours and puts the aircraft out of commission for a few weeks.
good. I don't want someone to update the software and next day send it in a commercial flight.
As long as the hardware has been tested, and the software update tested on different hardware, then as long as the test hardware and my hardware are nominally the same, and as long as the software has basic "self test the basics of every component on startup", then I don't see a reason to do more tests.