Two growth is normal.
THe third is unusual but if the plant do not feel it is time to rest it will grow. It may sound bad but you probably supply the plant with too good conditions as it sets the third growth. Maybe you should try to lowering the watering when the second growth mature and force the plant into resting. Though I belive it is more temperature and light that decide when a cattleya start it´s resting period.
I should add that I am speculating and have no hands on experience of your "problem".