Trying to wrap my head around how mob spawning/zones works when playing on a multiplayer server.

We have two small groups playing on the same server, at different times usually due to schedules, a "night" group and "day" group.

Since this started, when people from the "day" group login, we're finding things in our base area that indicate time is passing, e.g. torches/campfires out of fuel, damaged buildings, and in a couple of cases, a troll beating its way through the walls.

Even though the "night" group's base and players is a fair distance across the map, probably a quarter day's sprint away, would their presence cause mob activity in the "day" group's area while no one there was logged in?

Thanks!