Advance warning from principal teachers at university (5-2)

I believe the answer is:

heads-up

'advance warning' is the definition.
(I've seen this in another clue)

'principal teachers at university' is the wordplay.
'principal teachers' becomes 'heads' (headteachers).
'at university' becomes 'up' (slang term meaning at university).
'heads'+'up'='HEADS-UP'

'from' is the link.

I've seen this clue in The Telegraph.

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