A quick check as soon as the matter's settled (8)

I believe the answer is:

onceover

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'a quick check as soon as' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'matter's settled' is the wordplay.
'matter' becomes 'once' (I am not sure about this - if you are sure you should believe this answer much more).
'settled' becomes 'over' (I've seen this before).
'once'+'over'='ONCEOVER'

'the' is the link.

Can you help me to learn more?

I've seen this clue in The Globe and Mail.

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