Chris Bishop's been turfed out as National's campaign chair in favour of Simeon Brown - signalling a potential dent in his relations with the PM. 

The National MP's also lost his Leader of the House and Associate Sport Minister roles in yesterday's Cabinet reshuffle, but is replacing outgoing MP Judith Collins as Attorney General.

Former Minister and commentator Peter Dunne says Luxon might be trying to give Chris Bishop a warning on where he stands in the party.

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