Advanced in date, perhaps, as made up (6)
I believe the answer is:
atoned
'made up' is the definition.
(I've seen this before)
'advanced in date perhaps' is the wordplay.
'advanced' becomes 'on' (I can't explain this - if you can you should give a lot more credence to this answer).
'in' is an insertion indicator.
'perhaps' indicates anagramming the letters.
'date' anagrammed gives 'ated'.
'on' inserted within 'ated' is 'ATONED'.
'as' is the link.
Can you help me to learn more?
(Other definitions for atoned that I've seen before include "Made up for past offence" , "Made up for past wrongdoing" , "Made up for offence or sin" , "Made up for wrong done" , "Made redress" .)