My girl's nearly a year old now. She's currently a deeper steel blue and a rich tan/gold. Her mother was a light golden blonde with a silver body, while her dad had a deep rich tan head/face and black body. No idea on the colouring of her grandparents. I think she has her dad's eyes and her mom's facial features overall.
She certainly inherited more of her mom's temperament than her dad's from what I was able to tell from our couple hour visit.
If your current baby doesn't end up with your favourite colour combination in a few years, maybe then it's time for you to try picking up a second box of chocolates?
You can never have too many, right?
Unless, of course, your building and/or city are limiting your calorie intake.
The best bet would be to shoot straight for an adult yorkie with the colouring you like from the start. That way you can be sure of what you're getting. Problem is, that's no guarantee still as quite a number of them "lose" colour as they age, but I'm no expert.