what doed ''they’d hit Port Stephens'' means, thanks?
? A few came to ask me to marry them, but my father always said he could smell them before they’d hit Port Stephens and sent them packing.

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Answer

'They'd' is short for 'they had', 'hit' probably means 'arrived at', and 'Port Stephens' is the name of a place.
In other words, 'he could smell them coming from a long way away'.

Answer

In Australian vernacular "hit Port Stephens" means "arrived in Port Stephens", so the author is saying that her father could 'smell' them before they even arrived. He disapproved of them and sent them back home ('sent them packing').