Money back for a beer that's off - about time (6)
I believe the answer is:
rebate
'money back' is the definition.
(I've seen this before)
'a beer that's off about time' is the wordplay.
'that's off' indicates anagramming the letters.
'about' indicates putting letters inside.
'time' becomes 't'.
'a'+'beer'='abeer'
'abeer' is an anagram of 'rebae'.
'rebae' enclosing 't' is 'REBATE'.
'for' is the link.
(Other definitions for rebate that I've seen before include "price reduction" , "Beater (anag) -- partial refund" , "Sum paid back" , "Reduction in the cost" , "Money paid back" .)