Minecraft wiki entry for Redstone_Update, associated text: Development began shortly after 1.4.6 was released. Sixteen development snapshots were released, from 13w01a to 13w10b, with a few snapshots being quickly re-released straight after to fix bugs without changing the client version number. During the development period, 1.4.7 was released. Nearer the end of the snapshot cycle for the 1.5 update, Mojang focused primarily on fixing bugs, rather than adding new features.