A single occasion ever or confine a lie time break (4,2,1,8)

I believe the answer is:

once in a lifetime

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'a single occasion ever' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'confine a lie time break' is the wordplay.
'break' indicates anagramming the letters.
'confine'+'a'+'lie'+'time'='confinealietime'
'confinealietime' with letters rearranged gives 'ONCE IN A LIFETIME'.

'or' acts as a link.

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I've seen this clue in the Sydney Morning Herald.

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