The new Unreal Tournament 4 pre-alpha update has just recently been released, featuring the new Flag Run game mode. It also includes a new prototype weapon, the Lightning Rifle, as well as improvements to the Grenade Launcher prototype. UT is now on Unreal Engine 4.15, with all the associated new engine features and improvements. New user flow and training has been improved, and the main menu has also been refreshed. LAN servers can once again be launched from the menu. Quickmatch now uses a scaleable instance system and is no longer tied to hubs.
Flag Run which combines elements of the classic Capture the Flag and Assault game modes in an intense new round-based mode. It is still a work in progress, and all the playable levels are currently low poly shells. Flag Run is available as a Quickmatch option, on hubs, or even offline against bots. Also added are a training video and tutorial to help get players get up to speed quickly.
There have also been a lot of AI improvements, changes and improvements to other weapons, updates to the new community maps, new sounds, and many other updates and bug fixes. You can check here for a detailed change list. Also be sure to check out the patch video for a detailed explanation of the changes, additions and updates.