How is Delta approaching the increasing number of mechanical delays/cancellations driven by the over-use of the existing fleet? When will Delta return its planes to the regular maintenance schedule previously done?

Note, I live near a lot of Delta mechanics, several of which are friends. They are mostly 767 and 757 mechanics. I know from the horse's mouth that Delta has delayed maintenance and has had a much higher incidence of mechanical failures at the gate. Also note these are not safety related issues (hopefully).