Oppose return to university: student on vacation (4,2,7)

I believe the answer is:

come up against

'oppose' is the definition.
(to come up against something is to meet opposition)

'return to university student on vacation' is the wordplay.
'return to university' becomes 'come up again' ('up' can mean studying at university).
'on vacation' suggests removing the centre.
'student' with its middle removed is 'st'.
'comeupagain'+'st'='COME UP AGAINST'

I've seen this clue in The Guardian.

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