This is actually related to both OOB editor and Map editor.
As I interpret the reinforcements slider, this represents how many hours after the start of the battle the reinforcements will appear. So 0200 is two hours after the start of the battle, not 0200 hrs? I've got one reinforcement that continues to insist on showing up during set up regardless of where I set the reinforcement slider. Others it works fine for.
Also, is there currently no way to set where a reinforcement will enter from? I see that each force has two lines of operation so intuitively I expect to be able to have reinforcements arrive on one or the other of those points but I see no way to establish this.