Dishonored 2, despite coming out on Friday, has some copies out there in the hands of players, and one such player has revealed on Reddit that the day one patch for the game on PS4 is a sizeable 9.1 GB.
According to the same user, this patch is meant to fix things like texture streaming, bugs, shadowing quality, audio mix, frame rate performance and more.
Another source revealed that it would be around the same size on Xbox as well, and we can only assume this would address the same issues.
On PS4, then, the download will be 48 GB including the patch if you are downloading it digitally, so free up some space on your hard drive - you're going to need it. Do day one patches bother you?