Hello and welcome from Perth, Western Australia....(a very wet and stormy Perth today....our phone's out, but the internet survives Yay!).
Every time I visit here I learn something new....with the QB a mass of books and Youtube there's not much you miss out on.
Great to hear of your efforts with giant breed dog rescue. About a year ago pet shops here were full of Mastiff/Mastiff mix puppies....now there are so many of them looking for new homes its tragic.