I do not want to chang the time it starts spawning but the area you can walk before it starts spawning. Is it in te world files or spawning or game events?
For multiplayer, there is a server config that handles player safe zones based on their level, time playing, and if they have placed any beds (spawn points). It adds a "lock" to any chunks the player enters, which delays all enemy spawning until the safe zone timer runs out.
Code:
<property name="PlayerSafeZoneLevel" value="5" /> <!-- If a player is less or equal this level he will create a safe zone (no enemies) when spawned -->
<property name="PlayerSafeZoneHours" value="5" /> <!-- Hours in world time this safe zone exists -->
