With some inside knowledge these aircraft are not maintained to spec, crew duty time regulations are "make it up as you go along", i.e. 'Commanders Discretion' is persuaded by an X amount dollar bill, I mean I worked for a cargo operator and when I dared to suggest to the charterer, anyone around here named 'Chapman' and/or 'Freeborn'. that a crew be allowed a legal rest period I was flamed regarding and formally complained about by that charterer to my senior management.
Now go figure why such airframes fall from the sky and go try figure how such 'cowboy' charterers sleep in their beds of a night!