The official "Update 1" was intended to fix missing cutscenes, developer textures left in maps, and lighting (cubemap) issues.
Downloading game updates via .rar parts from non-official sources exposes your system to trojans, miners, or ransomware.
This specific file name is historically linked to the release of the game's first major update. Release Date: Roughly February 2018.
Blocked Drains Andover