Departure times going quickly (7,2)

I believe the answer is:

sailing by

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'going quickly' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'departure times' is the wordplay.
'departure' becomes 'sailing' (sailing is a kind of departure).
'times' becomes 'by' (both can mean 'multiplied by').
'sailing'+'by'='SAILING BY'

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I've seen this clue in The Independent.

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