Departs after various tree lines joined up again (2-8)

I believe the answer is:

re-enlisted

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'up again' is the definition.
I can't judge whether this defines the answer.

'departs after various tree lines' is the wordplay.
'departs' becomes 'd' (abbreviation eg in train timetables).
'after' says to put letters next to each other.
'various' indicates anagramming the letters.
'tree'+'lines'='treelines'
'treelines' is an anagram of 'reenliste'.
'd' put after 'reenliste' is 'RE-ENLISTED'.

'joined' acts as a link.

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I've seen this clue in The Independent.

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