Up to the time of (5)
I believe the answer is:
until
'up to the time of' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for until that I've seen before include "Pending such time as" , "Unlit (anag.)" , "Up to (a point in time)" , "As late as" , "Before a given time" .)