A Schedule Is A Moving Object

-- 1 He was behind (the) schedule.

-- 2 He finally caught up to schedule.

-- 3 Then he got ahead of schedule.

-- 4 The class was trying to keep up with the schedule.

Note: Motivation: a schedule defines a sequence of events, and eventsare understood to consititute a moving object.See Events file For some reason, we often use "schedule" as a max+ N, and do notuse a determiner with it.