Planes require lots of maintenance not sure why everyone is saying Boeing is the cause of this one. How old is the modified aircraft? If it’s a few months off the assembly line and it’s having maintenance issue that is grounding the aircraft then yea give Boeing some shit but airlines/operators have to take planes out of service all the time for maintenance, shoot even the military does it.

I worked in Aerospace for a few years and the company I worked for did a lot of work for Boeing, mostly on the Apache program, Boeing definitely has its issues but maintenance issues are not a Boeing only issue.