So far, it looks as if Oliver Lewis’s sudden departure as head of the Union Unit at Downing Street came down to a matters of personnel rather than policy, a casualty of the complex mess of court factions vying for the Prime Minister’s ear that our editor examined at the weekend.

This isn’t surprising. Having hand-picked the Vote Leave veteran to head up his Union strategy, it would be surprising if Boris Johnson suddenly found that he disagreed with his proposals. If there was a division, it seems to have been between the attack dogs and others, such as Michael Gove, who preferred not to stir the SNP up and to avoid allegations of ‘power grabs’.

(And indeed, we now hear that the Chancellor of the Duchy of Lancaster has circulated a note to Cabinet emphasising the importance of a new project he’s been working on regarding ‘inter-governmental relations’ between Westminster and the devolved executives. What timing.)

But personnel decisions can have policy consequences, and there are at the very least people in Government who want to signal a change of course. The Times has been briefed  that the move represented a return of ‘grown-up government’, which in practice seems to mean undermining the Prime Minister’s (perfectly justified) determination to refuse the SNP a second referendum and dusting off uninspiring non-solutions such as a constitutional convention.

This contrasts strongly with the stance taken not only by Lewis but his predecessor, Luke Graham, who opened a recent article thus:

Much ink has been spilt on the problems faced by the Union, and solutions are hard to find without falling into the well-rehearsed arguments for federalism or simply handing more powers to the devolved administrations — both options I oppose. For my part I believe the strategy of giving nationalists more powers is as effective as giving a bully your lunch money — it will never satisfy their desires and will entrap you in a prism of fear and powerlessness.”

Rather than ‘just saying no for ever’, Lewis’s plan was seemingly built around a couple of core aims: to shift the battle with the separatists onto favourable turf, and to build up Whitehall’s capacity to actually coordinate and implement the subsequent campaign.

The first part would involve both new policies, built on research which suggested that existing pro-UK efforts were failing to tap into important arguments and wells of feeling amongst the electorate, and a new approach. The experience of bringing the UK Internal Market Act to the statute book in the teeth of SNP opposition had shown both that voters really are just not especially interested in the finer points of the devolution settlement and that the SNP, having been allowed to go on the offensive for so long, was an underwhelming foe when forced onto the back foot.

Meanwhile, the lessons learned getting Britain ready for leaving the European Union – and more specifically, getting Whitehall in a fit state to get Britain ready – would be applied to Union policy, rather than having orders from Graham or Gove getting lost or bogged down in inter-departmental haggling.

It’s now not clear what the status of any of this is, nor that Johnson is prepared to give anyone the sort of authority they would need to drive such an ambitious programme through against inevitable opposition from the business-as-usual brigade.

Indeed, we hear that there may not actually even be a successor to Lewis at the Union Unit, which may instead be replaced by a Cabinet committee bringing together Johnson, Gove, Rishi Sunak, David Frost, and the three territorial Secretaries of State, not one of whom will have the Union as their full-time responsibility. (Guido confirms this.)

All of this has not gone down well with many backbench Conservative MPs, who are concerned not only at the unprofessional impression given by the churn at the Union Unit but also by the mooted shift in tactics. Some were not aware until now of the divisions inside the Government over the correct approach, and few are well-disposed towards the conventional, conciliatory strategy hinted at by the Times.

Independent pro-Union campaign organisations are also disappointed, and several have apparently reached out to Lewis to see if elements of his strategy can be implemented without Downing Street’s imprimatur.

We journalists are sometimes accused of paying too close attention to inside-baseball stories such as who’s in and who’s out at Number Ten. It’s certainly true that they shouldn’t matter terribly much – and if these advisers were merely the agents of a strong prime ministerial will, they wouldn’t. But if Johnson really is prepared to see his entire policy on a key issue hinge on them, hirings and firings will remain events of outsize importance. Only he can change that.