V8 Supercars CEO James Warburton has confirmed Tasmania is yet to be locked in as part of the 2015 Championship calendar.
The category's latest three-year contract with the Tasmanian State Government to run a Championship round at Symmons Plains expired after this year's race and has yet to be renewed.
Tasmania's newly elected Premier Will Hodgman declared to the media on race weekend last March that he wanted to extend the deal.
However, if that does not happen in the next five weeks the event is not assured of featuring on the draft 2015 calendar, which Warburton is currently developing with V8 Supercars' Chief Operating Officer Shane Howard.
That does not mean Tasmania won't still have a chance to see the V8 Supercars in 2015 and beyond, but with as many as three international events possible there is a chance it may miss out.
The final 2015 calendar will be issued in September.
New local permanent circuits proposed for Tailem Bend in South Australia and Toowoomba in Queensland are also chances to join the calendar in the next few years, adding more pressure into the mix.
Symmons Plains first hosted the Australian Touring Car Championship in 1969 and has only missed out since then on the big bangers between 2000-02.
Warburton stressed V8 Supercars wanted to do a new deal and ensure Tasmania stayed in the Championship.
"The Premier is supportive of an extension," he told v8supercars.com.au.
"For us to continue there are key safety elements and facilities that need to be closely looked at. It's not all in our court, some elements are in theirs."
The V8 Supercars is Tasmania's largest single sporting event, attracting 52,766 fans over the course of three days this year.
Warburton has a view the ideal calendar size is 16 events going forward. In 2015 there are 15 events including the non-Championship races at the Formula 1 Rolex Australian Grand Prix.
That could be come a Championship event in 2016 because of new telecasting arrangements for V8 Supercars with Foxtel and Network 10, while a 16th event could be added if two events are twinned in North America a week apart.
"We're in discussions with the Australian Grand Prix about a Championship round which we are keen to foster, depending on what happens with the future Formula One television rights," Warburton said.
"If you end up with a twin in America that makes for 16," he added. "Adding a second race in the US makes sense as you are already there."
Warburton confirmed Sydney Motorsport Park's 2014 return to the Championship was at this stage confirmed for a single year only, while Barbagallo Raceway in Perth has one more year to run on its current contract.