A marginally shorter Big Bash League window and a domestic 50-over tournament played in two pre-Christmas blocks either side of the Sheffield Shield rounds are looking increasingly likely as Cricket Australia gets close to finalising the schedule for next summer.

Earlier draft ideas had included the delay of the start of the BBL until Boxing Day and the scheduling of a post-BBL block of state one-day matches immediately after the T20 tournament, but ESPNcricinfo understands that more advanced planning has evolved into less drastic changes to the way the domestic season is mapped out.

According to plans currently under discussion, the season would commence with a block of 50-over matches, before the format switches to the four-day Shield competition, then back to 50-over matches before several more Shield rounds leading up to mid-December, meaning six rounds of the Shield in all would be played pre-Christmas, as was the case this season.

The BBL, while unable to be reduced from the 59 games contracted with the broadcasters Seven and Fox Cricket, will occupy a slightly shorter window of days, set to begin around December 23 rather than the December 19 start date of this summer's tournament. Any reduction in the number of days occupied by the BBL will necessitate an increase in the number of days in which more than one match is played.

How the season could look

October-November: Women's Big Bash

Late September-mid December: JLT Cup-Sheffield Shield-JLT Cup-Sheffield Shield

November-early January: International cricket

Late December-mid February: Big Bash

February 21-March 8: Women's T20 World Cup

Late February-late March: Sheffield Shield

As previously reported by ESPNcricinfo, CA's planners had looked at a scenario whereby up to seven rounds of Sheffield Shield cricket would be played before Christmas, while the 50-over tournament would be played in two blocks, one prior to the start of the Shield and another following the end of the BBL.

However, the concept of playing seven Shield fixtures more or less back-to-back before the halfway point of the season was seen as too much of a strain on fast bowlers in particular, as noted by the national team coach Justin Langer following the end of the home international season.

LISTEN: Talking T20 podcast - Big questions about the Big Bash

"There's no perfect answer to this," Langer said. "If you have seven Shield games before Christmas, that's a massive impact on the bowlers, especially off the back of a World Cup and an Ashes and an Australia A tour. Trying to keep our bowlers on the park has been a battle traditionally. Seven Shield games is going to put enormous strain on the bowlers."

The BBL, meanwhile, is set to continue to push out into mid-February, although discussions remain to be had about whether the qualifying matches are kept in the school holidays window up until the end of January before the BBL finals are stretched out over successive February weekends.

Numerous clubs are also believed to be agitating for a change to the finals system, whereby the top two teams play a qualifying final and the third and fourth teams an elimination final, before a preliminary final to decide the second finalist. This system, variations of which are commonly used in AFL and rugby league in Australia, would give the top two teams the reward of a double chance after Hobart Hurricanes became the latest frontrunner throughout a tournament to be knocked out in an elimination semi-final.

Kim McConnie, CA's head of the BBL, has made it clear that tournament organisers are open to tweaks and changes from one season to another. "We're fans first and we do listen to fans," she told AAP this week. "What do they think of the finals? What would they like to see? We don't evaluate by talking to ourselves.

"Our DNA is being innovative. We've got no qualms saying 'that worked really well, let's double down' and 'that didn't work, let's do something different'. We're going to wait for finals to end then spend a lot of time reviewing, talking to stakeholders and making changes."