... caused delay to inside promotion (6)

I believe the answer is:

putoff

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'caused delay' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'to inside promotion' is the wordplay.
'inside' indicates putting letters inside.
'promotion' becomes 'puff' (I've seen this before).
'to' placed inside 'puff' is 'PUTOFF'.

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I've seen this clue in The Irish Times.

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