I don't think they are recycled. Rich knows that would be a bug, not a
feature, and thus far there are only 1,500 controlled units.
> It could also be that the player who controled this noble allowed a new
> player to use Persuasion [Bribe Noble] on it, costing the new player
> the same number of NPs, but saving him a great deal of time.
Oath-2 nobles cannot be bribed. See the rules.
-- Oleg