It is said that you can never tell the true colour of an Afghan until the day he dies. Although it is relatively easy to spot a black masked red or other such colour, it is sometimes not that easy to tell the various shades of brindle. It is perfectly normal for an Affie to change the shade of his coat, but I've never heard of a black masked red Afghan turning into a black and tan! One of my dogs could be mistaken for a black and brindle, until he stands next to a true black. Then it is obvious that he is really a blue and brindle!
The Afghan Hound is a natural borm thief! Away back when the British invaded and tried to hold the countries of Afghanistan and India, the Afghan natives would send their dogs into British army camps to snitch food from the kitchen tents. Affies were also trained to take down anyone riding a bicycle, ostensibly to keep messages from reaching their destinations. Since the Afghan of today has never really forgotten his origins as a survivor, we still see these traits in modern dogs. Most Afghan owners love the challenge of trying to outfox these wiley hounds. Few of us actually succeed.