Prepared ahead to deliver scam (5,2)

I believe the answer is:

ready up

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'deliver scam' is the definition.
I know nothing about this answer so I can't tell whether this works.

'prepared ahead' is the wordplay.
'prepared' becomes 'ready' (similar in meaning).
'ahead' becomes 'up' (similar in meaning).
'ready'+'up'='READY UP'

'to' is the link.

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I've seen this clue in The Guardian.

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