Public certainly not in order (3,2,6)

I believe the answer is:

out of course

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'not in order' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'public certainly' is the wordplay.
'public' becomes 'out' (out can mean released to the public).
'certainly' becomes 'of course' (both can be used to answer in the affirmative).
'out'+'ofcourse'='OUT-OF-COURSE'

Can you help me to learn more?

I've seen this clue in The Independent.

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