Assassin's Creed: Unity arrived yesterday as a sizable 6.7 GB download. At least, that's the case for non-Xbox One players; some players using the Microsoft console are facing 40 GB downloads for the patch, effectively the size of the full game on the system's hard drive. Ubisoft explained the situation in an update on its support site, noting the "issue with the patch downloading process is replacing the entire game instead of just the parts affected by the patch."
The publisher is "working with Microsoft on a solution to reduce the total download to the intended size so that you can get back into the game faster," though it does not have an estimated timeline for the patch's fix just yet. Ubisoft did provide an alternative workaround for disc-based Assassin's Creed: Unity owners: By uninstalling and then re-installing the game, the patch will revert to the correct 6.7 GB download size. The publisher briefly delayed the launch of the patch earlier this week to "refurbish" the game's Paris map. The update is expected to fix ""most of the remaining issues [Ubisoft's] players have been reporting."