Times going after fellow being dishonest; it's happening very quickly (6,2)

I believe the answer is:

flying by

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'happening very quickly' is the definition.
I can't judge whether this definition defines the answer.

'times going after fellow being dishonest' is the wordplay.
'times' becomes 'by' (both can mean 'multiplied by').
'going after' says to put letters next to each other.
'fellow' becomes 'f' (abbreviation - of a society etc.).
'being dishonest' becomes 'lying' (synonyms).
'f'+'lying'='flying'
'by' after 'flying' is 'FLYING BY'.

'it's' is the link.

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I've seen this clue in The Irish Times.

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