Hi @johnsmith949,
ESS start‑up concession shares and options are taxed under the capital gains tax rules, the same way as other CGT assets.
When you cease to be an Australian resident, a CGT event happens to your assets that aren't taxable Australian property. This creates a deemed disposal at the time you stop being a resident. You can choose not to have this deemed disposal apply to all your non-taxable Australian property assets, but this is a single global choice. You can't make different elections for different asset types.
This means you can't treat your ESS start-up interests separately from your other illiquid assets.
You need to consider the CGT implications for all your non-taxable Australian property assets together when you cease residency. The choice you make applies to all these assets as a whole, not individually.
Have a read of the info we have under our ESS guidance for employees.