Activator Rails Doesn't Update Oriantation If Minecart is near

If you place an Activator Rail under a minecart so it recieves power when you place it, it doesn't update it's orientation and stays going north/south.

If you place the track any other way, it works as intended. It only happens when a minecart is near the spot the track will occupy.

Also occurs on sloped tracks as well, but is harder to reproduce.