Working with prohibitionist, settle ashore (2,3,4)

I believe the answer is:

on dry land

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'ashore' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'working with prohibitionist settle' is the wordplay.
'working' becomes 'on' (e.g. a machine is working or on).
'with' means one lot of letters go next to another.
'prohibitionist' becomes 'dry' (synonyms).
'settle' becomes 'land'.
'on'+'dry'+'land'='ON DRY LAND'

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

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