did the Holiday Is observe DST after the rest of Queensland stopped?

According to the current tz database, Queensland stopped observing DST after summer 1991/1992. But the IATA SSIM (which I'm currently slogging through, thanks to Gwillim Law) says that the Holiday Islands (Hayman, Lindeman, Hamilton) observed DST through 1993/1994. Does anyone know the true story here? If the IATA is right, we'll need a new entry Australia/Hamilton to handle the anomaly. I know that those islands exist (they're mentioned in <URL:http://www.lonelyplanet.com/dest/aust/gbreef.htm>, which says Hamilton has the most people) but none of them are in my Rand McNally Goode's World Atlas or in Shanks's International Atlas, so I'll need further info to find Hamilton's latitude and longitude.