Emerges from underwater when queen upset ocean-board champions (10)

I believe the answer is:

resurfaces

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'emerges from underwater' is the definition.
I can't tell whether this definition defines the answer.

'queen upset ocean-board champions' is the wordplay.
'queen' becomes 'ER' (abbreviation for Elizabeth Regina).
'upset' says the letters should be written backwards.
'ocean-board' becomes 'surf' (I can't justify this - if you can you should give a lot more credence to this answer).
'champions' becomes 'aces' (I've seen this before).
'er' back-to-front is 're'.
're'+'surf'+'aces'='RESURFACES'

'when' acts as a link.

Can you help me to learn more?

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

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