https://www.gamespot.com/articles/metro-exodus-delayed-for-ps4-xbox-one-pc/1100-6458978/

Metro Exodus, the third game in the survival/horror/stealth/shooter series and the first to feature a more expansive open world, has been delayed. The PlayStation 4, Xbox One, and PC game was originally due to launch this year, but it's now coming in Q1 2019, according to a press release from THQ Nordic. That works out to sometime in the January-March, 2019 window.

The developers told GameSpot that the team wanted to spend more time refining the game and polishing it to give players the best experience possible. As a result, a delay was needed.