Hi, I was quite interested in this as well, did some digging on hawaiian airlines, and looks like you can purchase upgrades if available 24 hours before flight using OLCI. Cost is $550-$700 depending on peak/off-peak. Can't link but if you google hawaiian airlines upgrade it'll be one of the top links.
[h=3]International (Business Class)[/h] [h=4]Australia[/h] [TABLE="class: tbl"]
[TR]
[TH][/TH]
[TH]Off Peak
Feb 01 - Mar 31
Nov 01 - Dec 09[/TH]
[TH]Peak
Apr 01 - Oct 31
Dec 10 - Jan 31[/TH]
[/TR]
[TR]
[TD="class: tabletitle, colspan: 3"]Australia to USA[/TD]
[/TR]
[TR]
[TD]AUSTRALIA to HNL[/TD]
[TD]550 AUD[/TD]
[TD]700 AUD[/TD]
[/TR]
[TR]
[TD]AUSTRALIA to Neighbor Island[/TD]
[TD]600 AUD[/TD]
[TD]750 AUD[/TD]
[/TR]
[TR]
[TD]AUSTRALIA to N.America
*excluding JFK[/TD]
[TD]899 AUD[/TD]
[TD]1,099 AUD[/TD]
[/TR]
[TR]
[TD]AUSTRALIA to JFK[/TD]
[TD]999 AUD[/TD]
[TD]1,500 AUD[/TD]
[/TR]
[TR]
[TD="class: tabletitle, colspan: 3"]USA to Australia[/TD]
[/TR]
[TR]
[TD]HNL to AUSTRALIA[/TD]
[TD]585 USD[/TD]
[TD]735 USD[/TD]
[/TR]
[TR]
[TD]Neighbor Island to AUSTRALIA[/TD]
[TD]635 USD[/TD]
[TD]785 USD[/TD]
[/TR]
[TR]
[TD]N.America to AUSTRALIA *excluding JFK[/TD]
[TD]934 USD[/TD]
[TD]1,134 USD[/TD]
[/TR]
[TR]
[TD]JFK to AUSTRALIA[/TD]
[TD]1,235 USD[/TD]
[TD]1,535 USD[/TD]
[/TR]
[/TABLE]