From same site:
3. Rich Bicolour, Melanistic Bicolour, faded bicolour.
Typically, the bicolour is a black dog with tan points much the same as a doberman. It is in fact the same gene. A very dark one with a strong black mask and much extension of the black may appear to be solid black, with a black undercoat and only some tan shading on the feet. Theoretically, bicolours always show tan around the vent, but I have seen a virtually black dog with just enough tan around the vent (and between the toes) to suspect that it was a bicolour, but not enough to be sure. However, a pale bicolour can look strikingly like a black sable, showing much black over a light grey undercoat, with tan or grey over the nape of the neck and along the harness lines, and black markings on the legs and feet. These dogs have the genetics for fading of the black mantle, and while they can still appear dark to the eye, will produce colour fading.
the "rich" bicolor shown is what most people consider a bicolor and not a bl/tan.
Pups with saddles will get them as the get older as the color will fade into a saddle if thats what they genetically were born with. You would need to know the parents and what was behind them.
Sables can get darker or lighter. Depends.