A reason for the delay was not announced.
Here is an overview of the game, via Reef Entertainment:
Terminator: Resistance Enhanced is a new version of Terminator: Resistance taking advantage of the new capabilities of the PlayStation 5 console. Jump back into the action with Jacob Rivers and experience his story from lowly private to hero of the Resistance once more, while enjoying improved framerates and graphical fidelity, faster load times, and the new hardware features of the DualSense controller. Terminator: Resistance Enhanced will also contain updates brought to the title on PC (Steam), as well as the brand new “Infiltrator Mode” which sees players get under the skin of the series’ iconic T-800 series Infiltrator.
- A fully updated version of the main game including balance and difficulty patches previously released on the PC. Players who own a PlayStation 4 version of the game will also receive a free upgrade to the PlayStation 5 version.
- New “Infiltrator Mode” in which players can get under the skin of a T-800 series Infiltrator unit and strike out against Resistance forces.
- A range of visual improvements taking advantage of the PlayStation 5’s more powerful hardware, including upscaled 4K resolution and locked 60 frames per second, higher resolution textures, higher polygon counts, tessellation, improved lighting and dynamic shadows, improved post-processing (antialiasing, bloom, and more), and more detailed particle effects.
- A variety of features new to PlayStation 5 including Game Activities which can be used to track the player’s progress in missions and trophies, DualSense adaptive triggers for weaponry, and color shifting within the DualSense light bar to reflect the player’s health.
- Four-times faster load times on average.
- Two physical editions available for the PlayStation 5 version of Terminator: Resistance Enhanced: a Standard Edition, and a Collector’s Edition, which includes a Steel Book, two-part hardback comic book “Zero Day” from Dark Horse (comic text in English only, previously available in digital format with the PlayStation 4 and Xbox One versions of the game), as well as four character art cards and a collectors box.
- A paid downloadable content expansion with new narrative content will also be available in Summer 2021 for the PlayStation 5 and PC versions of the game.