Maybe this time you should hit her with a Notice To Comply which carries the possibility of a fine ans well as a renewed notice to quit. Whatever the CTTT notice says, she's taking the mickey. The tenant is also clearly in breach of her tenancy agreement so she should be getting a separate notice to quit from the owner. If the dog is still howling, I'd also be calling the council Rangers and the RSPCA – leaving a dog, the most sociable of animals, on its own all day is downright cruelty. Sounds like this tenant thinks she can do what she wants because she reckons she's a lot smarter than everyone else. So hit her with everything you've got (figuratively speaking, of course) – thet might make her think again.