Record how long left in permit (3,4,3)

I believe the answer is:

all time low

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'record' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'long left in permit' is the wordplay.
'long' becomes 'l'.
'left' becomes 'time' (I can't explain this - if you can you should give a lot more credence to this answer).
'in' is an insertion indicator.
'permit' becomes 'allow' (synonyms).
'l'+'time'='ltime'
'ltime' going within 'allow' is 'ALL TIME LOW'.

'how' is the link.

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I've seen this clue in The Times.

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