Remember, the winter schedule has a daily flight between YVR and HNL with a more [tourist] convenient midday scheduled arrival/departure. I suspect AC is channelling any direct passengers onto this flight, and just putting through SYD passengers onto the traditional late afternoon/midnight one. Same with the new YYC service which is not intended to connect with the SYD flights, but to handle the tourist trade.

Makes sense to segregate bookings this soon in the season, so AC isn't losing any business, Empress, just responding sensibly with flights to HNL that also connect to/from inter-island flights.