I'm sorry to hear about your loss, but while we are on nostalgia - this is the original floor-refresh system. Exactly as it was back in the days. Some tiles are marked as refreshable, some tiles are not. Those that are refreshable - they are refreshed several times during the day if there are no players nearby, plus every server save. Those that aren't refreshable though - they are not refreshed at all, not even during the server save, allowing you to store your loot for days or even weeks. Unless someone else finds it, of course :) or unless a big map update occurs.