The 20-year-old was informed on Wednesday that countryman Chris Pither will take over the #111 Ford for the event as the squad evaluates the Dunlop Series runner for the seat in 2016.
Pither is thought almost certain to score the drive next year thanks in part to his ability to bring more backing than his predecessor.
The move is part of owner Tony Lentino's bid to make the outfit a commercially viable operation after funding the bulk of the near $2.5 million cost to run the car from Prodrive himself this season.
“It's obviously very disappointing what's happened,” Heimgartner told Speedcafe.com of his situation.
“We'd put so much effort in during the year and would have liked to continue on but there's not a lot I can do.
“Super Black has helped me out a lot throughout the year so I can't really object to them forward-thinking and worrying about what they're doing next year.
“Obviously money is a big part of it nowadays and I would assume what they're doing with Chris Pither has something to do with that.
“I'm grateful for the opportunities I've had and am hopeful of being back in the car at Homebush.”
Heimgartner says he'll be on hand this weekend to help the team wherever possible, including assisting Pither.
“It depends what Chris and the team want, but I'll be there hanging around and taking an interest during the races,” he said. “I'll be there offering all the help I can give.”
Although insisting that nothing is off the table at Super Black for next year, Heimgartner will also use the meeting to speak with other teams along pitlane that still have vacancies.
The bulk of the field is now set, but seats at Brad Jones Racing and Lucas Dumbrell Motorsport remain unfilled, while Ash Walsh's position at Erebus is now under serious question.
Heimgartner says losing the chance to shine at Phillip Island weakens his position in the market, but that he is still working hard to find a way onto the 2016 grid.
“I think Super Black have a few people that they're still talking to and I'm talking to a few myself,” he said.
“We're still a while away from signing anything from anyone, just with sponsors and a few other things.
“I'm just hoping I can get back in the car and have a good run at Homebush which will help things a little bit.”
With age well on his side, Heimgartner notes that a year combining GT racing with a Pirtek Enduro Cup co-drive would not be a disastrous outcome for his career.
“At the moment we're still working hard on the main game, but if we don't (get a drive), we'll look at the GT championship and things like that,” he said.
“GT is obviously getting quite big now, I wouldn't say it's a step backwards (from V8 Supercars).
“There's a lot of really good cars and a lot of money being invested, I think it's impressing a lot of people the way it's growing.
“It's appealing as well because you can go to Asia or Europe with the same cars. It opens more doors overseas than Supercars does.”