This is frequently done when parts become too difficult/expensive to maintain, but replacement from scratch still takes many months. Pretty much every part of

This is frequently done when parts become too difficult/expensive to maintain, but replacement from scratch still takes many months. Pretty much every part of the west is having problems with long elevator/escalator outages these days because so many escalators/elevators were installed in the infrastructure boom of the 1960s/1970s. They're now all reaching the end of their useful lives at the same time and they all need major overhaul and/or replacement.