>>498032910The story has a linear progression, but there's also side activities and calendar time management.
e.g. After you finish the tutorial prologue and have free run of the city you have a 10 day time limit to clear the story dungeon. You may spend that time doing activities that raise your Royal Virtue social stats, which when high enough will unlock access to more resources like the ability to upgrade equipment, or doing sidequests, which include things like another optional dungeon.
Also the time management works based on actions, rather than a real time cycle, like "if you travel to the dungeon, you won't make it home until nightfall, and be too tired to do anything else today" or "If you speak with this person you'll spend the entire afternoon with them, and progress to evening" which will be clearly marked and separated from things that you can do freely.