This is the problem with an Airline buying and operating too many of one type of aircraft. I remember reading a story where it stated that American Airlines owns 300 737-800's. Imagine if 50 percent of them require the 7 day inspection and 50 % of them are cracked. That would wreak havoc on Airline schedules and available seats. In my 45 years in aviation I do not ever remember a commercial airliner being grounded as long as the 737 MAX.