The players are fighting to clear their names, having been found by the Swiss-based Court of Arbitration for Sport to have been given thymosin beta 4 during the Bombers' 2012 supplements program.

It was hoped the players' appeal would have been resolved by the time the 17 footballers still in the AFL system rejoin their clubs and begin pre-season training in September. But a statement from the Swiss Federal Tribunal to Fairfax Media has cast doubt on this.

"We hereby inform you that the decision-making process is normally conducted in writing and it is too early to tell if the case will be decided in a public hearing," the statement said.

"There is no official time limit for the resolution of cases and we are currently unable to give you a time limit for the processing of this case. We will of course inform you if a public hearing will be held and as soon as the decision has been rendered.

"We confirm that the date for the final decision has not yet been set."

It's understood lawyers representing the players have the same information.

The players' appeal will be submitted in Swiss German, as they argue their case on points of law. Their lawyers argue that the CAS hearing should not have been allowed to have been heard de novo – or afresh – as it should have fallen under the World Anti-Doping Agency's 2010 code. But the WADA code was revised in 2015, and CAS used this upgraded model.

Players Jobe Watson, David Hille, Mark McVeigh, Cory Dell'Olio, Scott Gumbleton, Brent Prismall and Ricky Dyson were called before the CAS panel to give evidence when the hearing was held in Sydney.

While the result before the Swiss tribunal will not alter the suspensions the players have already served, a not guilty finding would help ease the stigma they continue to live with.

The CAS had been damning of the secrecy of the injecting program, although some players disputed this claim. The CAS report said their "behaviour, keeping the club doctors out of the loop, and failing to record the injections on the doping control forms, clearly justifies such inference being drawn. This was, at its lowest, consistent with an appreciation of its controversial nature."

Stephen Dank, the architect of the injecting program, insists he did not use thymosin beta 4.

The players are seeking compensation from the Bombers and the club' insurer for damages for health and safety breaches and loss of earnings.

It had also been hoped these claims would be settled before pre-season training resumes but some player agents believe this could drag on into 2017 – four years after the Dons self-reported to the AFL and the Australian Sports Anti-Doping Authority.