Ocean waves increase another time (4,5)

I believe the answer is:

once again

'another time' is the definition.
(synonyms)

'ocean waves increase' is the wordplay.
'waves' indicates an anagram.
'increase' becomes 'gain' (gain is a kind of increase).
'ocean' is an anagram of 'oncea'.
'oncea'+'gain'='ONCE AGAIN'

(Another definition for once again that I've seen is " encore".)

I've seen this clue in The Telegraph.

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