There's a banner on front page of their website advertising this. Click it for more info, but there's not much to it really.
Order before midnight tonight and get free next day delivery (before 5pm tomorrow).
No minimum spend.
Some examples:
$3 bottle of Red https://www.firstchoiceliquor.com.au/Red%20Wine/hidden-gem-c…
$3 bottle of White https://www.firstchoiceliquor.com.au/White%20Wine/hidden-gem…
$5.50 for 50ml of Bundy https://www.firstchoiceliquor.com.au/Spirits/bundaberg-up-ru…
Happy boozing!
edit: Looks like it's free metro delivery only, not regional or country.
edit 2: extended by 1 day (thanks Normie)
Was short on Red for the weekend, and couldn't be arsed to go to Dan's, so this deal to get a case delivered to work on the Friday before the weekend was as timely as they come. Thanks OP.
And for those wondering, no need to enter a coupon, you can just choose next day delivery at shipping options.