When Prime Minister Jacinda Ardern stripped Poto Williams of the police portfolio this week and reallocated roles held by outgoing MP Kris Faafoi, she also put her other ministers on notice.
The changes Ardern made in her reshuffle were something of a bare minimum. The tougher reshuffle will bethe one she makes in about six months' time when she has to negotiate between ministers who want to leave, those she might want to leave, and the bear pit of ambition in the middle benches.
Ardern's forewarning a larger reshuffle is nigh is effectively a signal to ministers to weigh up whether they have the appetite to stay – and engage in some frank self-assessment about whether they think Ardern has the appetite for them to stay.
Because if Ardern considered her first reshuffle minor, it indicates her second will be large.
Part of that will be to try to inject a fresh face and fresh energy into Labour – the unrelenting nature of Covid-19 has seen the Government age in the public eye much faster than a usual government would.
Doing that will mean something of a clean-out of ministers who may have got away until now with being a bit average.
Ardern has been shown to have quite a brutal and pragmatic streak when it comes to reshuffles.
There is little mercy if a minister is letting the side down.
Meka Whaitiri, David Clark, and Phil Twyford all found that out in the last term of Parliament. Once her confidence has been shaken, it has also proven very difficult to claw a way back. They may well be among those Ardern is hoping will consider their futures.
Ardern also now has the luxury of a wider, hungrier middle bench than in the last term of Parliament. But as Labour falls in the polls, she also has to keep them disciplined and happy; the chance of a promotion is one way to do that.
Ardern also needs to be sure that the most competent of those survive beyond the 2023 election when Labour will inevitably lose MPs after their extraordinary 2020 result.
Those she will be keen to protect include Rachel Brooking, Vanushi Walters, Barbara Edmonds and Camilla Belich.
Ardern's mini-reshuffle this week did contain some hints as to what might happen in her wider reshuffle.
Giving Kieran McAnulty an associate role in local government is likely to mean Nanaia Mahuta loses that portfolio in the reshuffle and is left to focus on foreign affairs. It is understood Mahuta is keen to shed local government, but Ardern wants the controversy of the Three Waters reforms to be dealt with first.
A change in six months would be a good time for a new minister to take on the wider reforms for local government without being so closely associated with Three Waters.
Hipkins may also lose his ongoing skirmishes to keep the education portfolio – he has won that battle twice because he is one of Ardern's MVPs. But whether he will win a third time in six months is less certain. Ardern giving a vast chunk of the schools portion of the education portfolio to Jan Tinetti shows where she wants that to end.
There will be room freed up for her by other ministers who decide to retire. In fact, Ardern's concern may well end up being that too much room is freed up.
Government in normal times is exhausting enough and burnout is a factor that will decide some of those ministers' fates.
Summer will be the critical time for ministers to weigh up whether they have the stomach for another term, especially if that term is in Opposition.
There are already rumours about whether Kelvin Davis intends to hang around. Health Minister Andrew Little may also well be turning his mind to the question of bowing out - the health reforms will be completed, he is unlikely to be promoted any higher and he may well look for another opportunity.
There is also speculation about Damien O'Connor - although he is perhaps the most valuable he's ever been to Labour in his political career and they will be wary of losing the West Coast seat.
Poto Williams is a cautionary tale for other ministers who are not necessarily on top of their portfolios.
As yet she has not been demoted from her 10th ranking in Cabinet, but that appears to be largely a matter of not wanting to give National too much satisfaction.
Williams should drop down the ranks a bit in the next reshuffle – the front bench have to be both competent behind the scenes and capable of performing on stage, that stage being Parliament.
The saga of Williams and National's Mark Mitchell is a salutary lesson in the merits of putting people into portfolios they are interested in.
Mitchell had been all but invisible prior to Christopher Luxon taking over the leadership and giving him the Police portfolio.
Mitchell transformed into the Incredible Hulk. He has gone about things with all the subtlety – and effectiveness - of a sledgehammer.
By contrast, Williams seemed to lack enthusiasm for the portfolio and failed the basic metric of ensuring it did not add to the troubles already on the Government's plate.
Mitchell has called the appointment of Hipkins "window dressing," arguing changing the person does not change Labour's ability to confront gang violence.
The selection of Hipkins – one of Ardern's top ministers – is partly about optics. It is partly a show that Ardern is taking the issue seriously enough to give it to one of her top performers.
But Hipkins is far less likely to end up looking bewildered and bamboozled under Mitchell's attacks.
He will have to take a long look at the policy settings – the perception is that Labour's law and order policy has not shifted in response to the changing gang landscape.
Those changes were starkly spelled out in police intelligence reports on what deportees from Australia had wrought on the New Zealand gang scene.
But Hipkins' job is not to transform Labour into a party that is hard-line on crime – it is to get the issue of Labour's management of crime out of the headlines.