Chief executives of cricket boards will start hammering out on Thursday what cricket's next eight-year calendar will look like. CEC (the ICC's chief executives' committee) meetings on the 2023-31 cycle have so far been exploratory in nature, in trying to suss out member views on various competitions, ICC events, and the growing space domestic T20 leagues now occupy.

But the real work of getting the calendar into shape begins now, with two broad questions to answer: One, how much time and space is available for bilateral cricket given ICC events and domestic T20 leagues. And two, what should the structure of international cricket, including the World Test Championship (WTC) and the ODI Super League, look like?

These discussions are likely to be more complicated than ever, and not just because figuring out a common virtual window for every board from around the world to attend is relatively tricky. The demands on the calendar are growing and have amplified, even in the time since these discussions last took place, across 2017 and 2018. Ahead of the meeting, we look at the four issues that need resolving in the next calendar.

The neglected middle format: ODIs

T20s and Tests are fairly settled for the moment but it's bilateral ODIs, and specifically in relation to global ODI events, that are under the scanner.

Ostensibly, the ODI Super League is providing context to bilateral ODIs with the reward of World Cup qualification at the end of it. But it has yet to gain real traction and momentum, given its start was postponed because of the pandemic, and the immediate focus is firmly on the two upcoming T20 World Cups. One of the points of discussion will be an expanded 50-over World Cup - with 14 rather than ten teams - though the push for this is coming from those Full Members who weren't in the last World Cup. Full Members like their teams to be in World Cups, as one official said, and there are currently 12 Full Members but a ten-team World Cup.

If there is a larger World Cup in 2027, what happens to the ODI Super League? Currently it features 13 teams, out of whom the top eight qualify directly for the 2023 World Cup. If it was kept to a 13-team league but eventually 12 qualified from it, that would defeat the point of a league.

If that league becomes larger - and for 12-14 teams to qualify, it would have to be much larger - then it starts eating into the calendar, which already has too little space in it. And there might still be an appetite for a World Cup qualifier tournament, given the great spectacle that the 2018 tournament in Zimbabwe was.

Nine or more for the World Test Championship?

Members see the WTC, by and large, as a success, enough in any case to indicate it will be around beyond the current cycle. The build-up to the finalists being confirmed, as well as the build-up to the final itself, has gone down well.

But the question hovering over the league is what to do with Zimbabwe, Afghanistan and Ireland. The three are not part of the WTC in the league's second cycle, which ends in 2023, but are keen to get some definition around their involvement going forward beyond that - even if it is a pathway that ultimately leads to inclusion.

When the league was first devised, those three teams weren't playing enough Tests to be part of it. They have only played nine Tests between them - Ireland none at all - since the WTC began in August 2019. They have a slightly busier Test calendar in the second cycle of the WTC, but not by much.

The challenge, again, will be limited calendar space. Six series (three home and three away) over two years for each team works currently. Adding more teams will mean somehow squeezing more time out of the cycle, or not playing more than the six currently stipulated series - which dilutes further the idea of a league, in that a growing number of sides won't play each other.

That extra ICC event

In some ways this extra event is at the heart of the game's current tensions. As things stand, the extra event - whether it is an ODI tournament or a T20 one - has been approved by the ICC board, despite objections from the BCCI.

But with CA and the ECB joining the BCCI in their opposition, and ICC chairman Greg Barclay suggesting an extra event was not a done deal, don't take it as final. It does have majority support among members currently - many of whom rely significantly on ICC event revenues - and is an acknowledged starting point for discussions, but whether that means it will still remain at the end of these discussions is a different matter.

And if it is an ODI event, that will only complicate the status of the ODI Super League. It used to be that ICC events would be scheduled into an eight-year cycle and members then went and built their own bilateral schedules around it. But with extra context now with the WTC and Super League - in essence, two more competitions - getting clarity on what they look like is just as important as knowing when - and where - ICC events will be played. Once members work out their bilateral match-ups in these competitions, a calendar can start to be built.

The other calendar

One of the main points of difficulty in the 2017-18 scheduling discussions were the various domestic T20 leagues that members were running - an alternative calendar to the year, essentially. At that time, South Africa's Mzansi Super League (MSL) and the PSL were difficult to work around, in that they took two elite teams out of international cricket for a total of six or so weeks in the October-March window - which is when the majority of the member teams are in their international season.

This time, add to those leagues the Lanka Premier League, the Afghan Premier League, the Abu Dhabi T10, from this summer on, The Hundred, and from 2022, an expanded IPL. That creates many more moving parts for members to juggle with. The ICC has no control over this, of course, but because they all eat into one calendar, it all has a direct impact on international cricket.

Osman Samiuddin is a senior editor at ESPNcricinfo