Long twelve months before end of recession (5)
I believe the answer is:
yearn
'long' is the definition.
('yearn' can be a synonym of 'long')
'twelve months before end of recession' is the wordplay.
'twelve months' becomes 'year' (I've seen this before).
'before' is a charade indicator (letters next to each other).
'end of' says to take the final letters.
The last letter of 'recession' is 'n'.
'year'+'n'='YEARN'
(Other definitions for yearn that I've seen before include "Desire strongly" , "Ache, crave" , "Mark of injury" , "Desire, want" , "Have a great longing" .)