The Dorothea Mackellar Memorial Society is currently "in limbo" waiting for work to progress on the garden restoration at Kurrumbede.
Society member Owen Hasler said he didn't think much would be done until early 2021.
This is because Whitehaven Coal is progressing through "a range of secondary approvals in relation to Vickery".
But a Whitehaven spokesperson said they were still continuing to engage with stakeholders on various aspects of the work, like having Kurrumbede heritage listed.
"We remain absolutely committed to the preservation of the homestead and ensuring we have the proper mechanisms in place to support eventual community access in co-existence with our Vickery project," they told the NVI.
The 6880-acre property borders the Namoi River, about 25km out of Gunnedah on the Blue Vale Road, and was the former family residence of the late poet Dorothea Mackellar. It's owned by Whitehaven.
In late 2018, the society submitted a nomination for it to be included on the state heritage register, making it eligible for government grants for maintenance.
Cr Hasler said the society was "still confident" the heritage listing would be successful.
"We understand a recommendation will be going to them and a decision will be made in the foreseeable future about that," he said.
The gardens in the vast grounds of Kurrumbede will be re-established with advice from the Office of Environment and Heritage (OEH), which the society and Whitehaven are waiting on.
A bore has also been installed specifically for the gardens to ensure water supply.
Whitehaven made a public commitment to the preservation of Kurrumbede in early 2019 and pledged $500,000 for the garden restoration two months later.