Steam releases have changed the order of things wrt 'north america vs europe vs everyone else vs Australia'. Usually in that order historically. For a few years now, major releases have followed either: block by block launch time (not specific to timezones, but rather 'Australasia->europe->north america') on the same day (Xcom or BE did this) but with 'local' (within the block) release times of midnight. or truly local midnight by timezone. Just depends on how big the game is expected to be wrt mass downloads/starts on the steam servers. 2K has been using that pattern already on steam, so it's unlikely to be an old style slow release. Worst case is the 10am PST (Valve morning), but that's only for smaller games or games without big publishers.