The loss of the Hall of Fame event is just the latest major development after a season in which the calendar became a moving target due to the effects of COVID-19.
Despite the worst of the pandemic seemingly over, Supercars faces another challenging task in determining how next year's tour will look.
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As yet, there is no word on when Queensland's border with New South Wales will reopen, nor Western Australia's hard border, or when the rest of the country will allow free entry from Victoria.
There is also the ongoing question over mass gatherings, which could affect the viability of street circuits in particular.
Speedcafe.com understands that several circuit operators/promoters are still awaiting firm details about their events, including when they might take place.
The West Australian Sporting Car Club, which operates Wanneroo Raceway and promotes the Perth event that is held in the city's north, is working towards hosting Supercars in one of two known ‘windows', but multiple other stakeholders have less certainty.
There is, however, generally understanding about the task which the championship faces, with one of those stakeholders saying they are “not surprised” by the situation.
The 2021 version is still not likely to emerge for at least another week, although its make-up is becoming clearer.
What is known is that the first event will be held in New South Wales, at an as yet unspecified circuit but widely expected to be Mount Panorama.
The NSW Government's announcement of the former news coincided with confirmation that the Bathurst 12 Hour will not be held next year, and came a day after Supercars CEO Sean Seamer told competitors from Mount Panorama's pit lane, “we'll get back here to Bathurst in February.”
It is likely to consist of a pair of 250km races based on comments from Seven West Media CEO James Warburton in a video presentation with Seamer, his successor at Supercars, released as part of the announcement of the new television deal.
A March 18-21 date seems most likely for the Australian Grand Prix, with the Supercars Championship field understood to be on the support bill and racing for points despite Network 10 holding Formula 1 broadcast rights.
F1 teams were presented a draft calendar on Monday and it is believed to be due for release next week, rendering an unveil of the Supercars calendar highly unlikely before then.
The Bathurst 1000 would be held on October 7-10 assuming it returns to its now normal position on the weekend after the Labour Day public holiday in NSW, having been pushed back a week this time around to give teams more time to prepare after months on the road.
The NSW Government has also confirmed that a Sydney SuperNight will take place for the next five years, although there are no strong indications yet as to when it might fall in 2021.
‘Eastern Creek' was originally slated to play host this year on August 28-30, and did so on August 3-4 in 2018, when Supercars raced under lights on Australian soil for the first time since the 1990s.
Planning is understood to be underway on the Darwin event.
Hidden Valley had come to ordinarily play host in mid-June before it was to have swapped positions this year with Townsville and take up a mid-July date, but ultimately saw two events in August after a quarantine saga.
Darwin's climate is such that Supercars is virtually locked in to a winter visit, making June or July highly likely again.
Supercars has indicated that it will return to New Zealand in 2021, despite that nation still being closed to foreigners.
Whether that is at Pukekohe or Hampton Downs, the latter of which was a hasty replacement for the former after it was discovered that racing in the Auckland region on ANZAC Day is prohibited, remains to be seen.
With hints already that Supercars was looking to prune its calendar, the death of the Adelaide 500 could mean a reprieve for another event.
The Bend is effectively the only other option for a South Australian presence, and plugged a hole in this year's season with events on consecutive weekends in September.
Newcastle debuted in 2017 on a five-year contract but, after missing out this year due to COVID-19, there are question marks about its place on the 2021 calendar.
All of those except Winton are the subject of multi-year contracts which were to have taken effect this year, but none of those except Townsville ended up actually hosting Supercars this year.
Both Townsville and the other Queensland venue in the Gold Coast are street circuits and while the former demonstrated this year that it is a relatively low-fuss temporary venue, its southern cousin is far more disruptive, as well as being intertwined with residential and hotel buildings.
Although there is no firm indication of when the 2021 calendar will come, the Racing Entitlements Contract deadline is understood to be late-November.
Actual and prospective competitors would presumably need some level of certainty over which and how many events they are facing before committing, meaning that day provides some sort of marker for the calendar.