This is the question that made the idea of McCullum replacing Matthew Mott seem like a non-starter from the off.

How can a man who lives in northern New Zealand commit to the relentless schedule of both England teams? Why would he want to?

The why is perhaps the easier bit. McCullum has always admitted his England gig is "the best job in the world". When in 2022 he took over a Test team that had just one win in 17 matches, he said he wanted a challenge. Combining both roles is certainly that.

It's not like McCullum only spent his downtime from England back at home with rugby, horse racing and wine. During last year’s 50-over World Cup, McCullum was in India as part of a business interest. An improvement on his England salary certainly wouldn't have hurt the deal, either.

The how is slightly more tricky, yet was alluded to by managing director Rob Key when he spoke to Sky Sports last Thursday. England's schedule is easing, meaning there will be fewer times when the Test and white-ball teams overlap.

There are also some practical elements that make it more doable for McCullum. England tour New Zealand both this winter and next winter, for Test and limited-overs matches respectively, so straightaway there are two series when he doesn't have to be away from home.

In reality, his two-year contract extension is little more than 18 months. He was due to finish in early 2026 after the away Ashes and now goes through to the 50-over World Cup in the autumn of 2027.

Naturally, he will need a breather from time to time. Marcus Trescothick is already interim white-ball head coach until the new year and may step up again. Paul Collingwood is another who could lead. Maybe England will take on another full-time assistant. McCullum's great mate Eoin Morgan would fit the bill, while Andrew Flintoff is working with the Test side for the series finale against Sri Lanka this week.

English cricket has been historically poor at exposing its best players to top-level coaching, so giving experience in this situation can only be a good thing in planning for life after Baz.