The time of day matters in Deathloop. Certain events and opportunities will only be available at specific times of day on Blackreef. The time of day will be next to certain Leads or Discoveries that Colt has in the game, and that means you need to be in that distract during that time of day for it to occur. If you’re not watching the time of day, you might be unable to interact with certain activities.
When a certain time of day is happening in a district, it will never change. You can explore that entire district in the morning, and afternoon or evening will never arrive. You’ll be able to do everything you want during that time. However, when Colt needs to swap between districts using the tunnels, the time of day will change.
While choosing your loadout, you can choose to wait for a certain time of day to occur. However, if night occurs, and you choose to start a brand new, you’re going to begin at the beach and have to start all over again. Any Visionary you killed will return, and everything starts back up again. Therefore, you may want to complete the Ubiquity Arsenal Lead before voluntarily restarting the day.
Thankfully, the one thing that keeps you with each day is the information you learn. You can always explore each of the night areas, learn something new, and start the days over again. While you might begin the new start with the same gear, you could acquire additional information to aid in your struggle to break the loop.