Crossword Genius

Unsettled duck in front of greenery when last rook departs (7)

Ross

I believe the answer is:

overdue

I'm a little stuck... Click here to teach me more about this clue!

'unsettled' is the definition.
(I've seen this before)

'duck in front of greenery when last rook departs' is the wordplay.
I cannot quite understand how this works, but
'duck' could be 'o' and 'o' is found in the answer.
'when' could be 'e' (I've seen this in other clues) and 'e' is found in the answer.
'rook' could be 'r' (abbreviation in chess) and 'r' is present in the answer.
'departs' could be 'd' (common abbreviation e.g. train timetables) and 'd' is located in the answer.
This explanation may well be incorrect...

Can you help me to learn more?

(Other definitions for overdue that I've seen before include "Later than expected" , "Opposite of 1 ac." , "unsettled" , "Beyond the designated time for payment" , "In arrears" .)

I've seen this clue in The Telegraph.
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