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No, you would need to go to barriers to touch out and then recommence your journey on a 'paper' ticket.
It may be possible to make a same train exit and touch in heading southbound if the train uses slow line platform 1 as that platform has a gateline on the platform.
Maps of the station layout are available on the National Rail website.
Not a chance in the northbound direction, and wouldn't be easy southbound unless you are: a) on a train calling at platform 1; b) positioned correctly for the gateline and c) not encountering hordes of witless tourists and their tons of luggage blocking your way.