Don't go a bit past a year (4)
I believe the answer is:
stay
'don't go' is the definition.
(I've seen this in another clue)
'a bit past a year' is the wordplay.
'a bit' indicates the answer is hidden within the clue (I've seen 'bit of' mean this).
'STAY' can be found hidden inside 'past a year'.
(Other definitions for stay that I've seen before include "Stick around" , "Remain; steady" , "Reside" , "guy giving > support" , "Linger" .)