When does the count start after you have defeated a nemesis boss?

Question

When you defeat a nemesis boss, the countdown for when the boss will appear again starts from the moment you've defeated it. For example, if you defeated boss X after day 1 at 7 am, and the respawn time for boss X is 5 days, the boss may reappear after day 6 at 7 am. Or the countdown starts at the server save of the day you defeated the boss, such as 3 am, boss X may spawn again after day 6 at 3 am.

Answer 1

Countdown starts after save server.

So if you for example killed boss at 20:00 (10h after ss) countdown for next boss right after next server save

Comments

How do you know that?