Oh, I know they can block more than once, Ming blocked several times. My vet just told me that many cats only block once and never block again. I thought it might been something severe that made them give Alani the PU surgery after only one blockage. A scarred penis is a very good reason. I am so glad you caught this when you did and that Alani will be fine. I am sending Alani, you, and all your precious kitties good wishes.