Unplanned tuition saved following reorganisation (12)

I believe the answer is:

adventitious

'unplanned' is the definition.

'tuition saved following reorganisation' is the wordplay.
'following' says to put letters next to each other.
'reorganisation' indicates anagramming the letters.
'tuition'+'saved'='tuitionsaved'
'tuitionsaved' is an anagram of 'ADVENTITIOUS'.

(Another definition for adventitious that I've seen is " Accidental - unexpected".)

I've seen this clue in The Times.

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