In a post on the PlayStation Blog, Naughty Dog staffers Neil Druckmann and Bruce Straley explained the reason for yet another delay.
"This is our largest Uncharted game to date," they said in the post, "and the team has been working incredibly hard to meet the challenge of closing out the game's development in a timely manner.
"However, as we approached our final deadlines and started wrapping up the game's levels, we realized that several key sequences needed extra resources to bring them to the finish line. After carefully considering all of our options, we decided to extend our schedule," they wrote.
This isn't the first time that Nathan Drake's inaugural PS4 adventure — and possible final outing overall — has been delayed. Naughty Dog initially announced the game as a late 2015 release before pushing the game to 2016 back in March.
The developer recently wrapped up the game's first multiplayer beta, giving players a chance to try out the long-awaited game. Uncharted 4 also made an appearance at this year's PlayStation Experience 2015 event earlier this month, where a new trailer showed off its usage of dialogue trees, a first for the series.
Just this past weekend, the game hit theaters alongside Star Wars: The Force Awakens, showing off pre-rendered footage in a special teaser.
Take a look at Uncharted 4 in action, courtesy of the E3 2015 footage below.