It's complicated, and they don't have the detail yet as they...

It's complicated, and they don't have the detail yet as they need to apply for a private ruling. They state " HUM
intends to distribute the sale proceeds in a tax efficient manner and has sought a ruling from the
Australian Taxation Office, which HUM expects will be issued after completion of the Latitude transaction."

It's more complicated as there will be both a new share allocation (LFS shares), which will likely affect the cost base of each share and I suspect will be offered to rollover, or be applied at the time, PLUS the cash distribution which will be CG taxable if taken as a return of capital. They will need to calculate theoretical values, and consider various distribution options so it's not possible to say what form it will take. However, you will likely need to do a calculation for this year's return, while updating your records and retain that update for inclusion when you also finally dispose of your HUMM shares, however far away that is, as it often involves an adjustment to your cost base i.e. what you originally paid for the shares.