Yet another alternative.

Canberra megabattery to hold 250MW. Onslow expected to hold....1000-1200MW?? depending on which news source you read (Newsroom v Stuff).

https://www.abc.net.au/news/2023-04-...ergy/102217104

"Expected to be online in 2025, the battery energy storage system will cost between $300 million and $400 million".
Looks like construction hasnt started yet.

....so one can be built in about 2 years? Maybe 4-5 of them would roughly match Onslow?? No birds or lizards displaced and maybe total under $2bn in a 2-4 year timeframe plus you could put them in the North Is where needed.
Just charge them during summer with a solar field.

There must be a catch of course, be interested to hear what that is from those in the know. I didnt see Contact's presentation refer to any alternatives.....
(thanks RTM by the way)