“This means that unless a motion is passed to defer this consideration (which appears unlikely), or the election is called beforehand, this bill will be brought to a vote when the Senate re-convenes as scheduled on February 4,” the association said.

“We still believe the government does not have the necessary Senate crossbench support to pass this bill. And with an election fast approaching, doing a ‘deal’ with the crossbench seems unlikely.

However, the SMSFA said it was important to differentiate between attempts at “horse-trading” to secure crossbench support and substantive amendments presented as addressing their concerns.

“At this stage it is unclear whether the government will propose amendments and risk further political capital on a policy with so many unintended consequences and which sets a dangerous precedent for future tax reform,” it added.

“Aside from allowing the use of actual taxable earnings (which appears unlikely), given the design of this tax, there is no ‘quick fix’ to the issue of taxing unrealised capital gains. Any amendments proposed are only likely to delay or marginalise the impact of taxing unrealised capital gains and will come with considerable complexity and cost.”

The association said the sector needed to remain vigilant and do what it could to ensure the Senate crossbench remained opposed to the tax.

“We will be in Canberra on February 4 to convey our concerns about ‘last-minute’ amendments, and to remind the crossbench once again of the far-reaching implications of this legislation,” it said.