Departed behind schedule (4)
I believe the answer is:
late
I believe this clue is a double definition.
'departed' is the first definition.
(I've seen this before)
'behind schedule' is the second definition.
(running late)
(Other definitions for late that I've seen before include "Dead or not punctual" , "Still to come - already gone!" , "No longer alive; tardy" , "Dead - tardy" , "Previous" .)