DC every 3h?

I'm playing on Icecrown and I have noticed that when I stay online for about 3h I get disconnected back to the login screen.
This has happened multiple times, I think I've read something about server kicking out players in busy areas to improve performance or something like that.
Don't know if that's the case. Still I get disconnected even if I just stay in some remote zone like Feralas and queue battlegrounds.

Is there some way to avoid this? Or is it just me?
I'm restarting the game when I remember before the 3h are up and that's only workaround I know right now.

From my own experience, aside from the occasional DCs (most of which are from my side) it's been no problem staying inside the game during ICC raids (the only case where I know that I stay in the game for 3h straight).

The 'busy location kick' happens only within Dalaran, and only to the character selection screen, so I don't think that's what's happening here either.

I have a stable fiber internet, I never used to get dc's on warmane, maybe 3-4 dc's over the whole time since 2009, but lately I got a dc every day, and it's client sided.

Exactly, his can't be a stability issue, game just DC instantly in the middle of the action. No lag, no freeze, everything is ok and boom: login screen with disconnected message.