Since I got some spelt flour at home, and I do like the nutty flavor it brings, I decided to replace some of the white flour with spelt flour in the recipe.  Due to my work/life schedule, I wasn't able to follow the time schedule used in the book (Reinhart's Crust and Crumb), but I did it anyway.  Fortunately, the bread turned out beautifully. Here is what I did (half of the recipe only):

Starter built-up

Medium starter (I used my rye starter): 8oz

White flour: 4.5oz

Add water as necessary

Final dough

All starter

White flour: 10oz

Spelt flour: 3.5oz

Water: 9oz

Salt: 0.39oz

Procedures:

I have the starter sat at room temperature for about 11 hours.  By the time I put the starter in the fridge, it had risen more than double.  After 33 hours, I took the starter out of the fridge.  The surface of the starter looked pretty dry (I did have it covered in plastic), but it smelled very nice.  I proceeded with the mixing, and 3 folds at one hour interval.  Then I divided the dough in two, shaped, let them proofed at room temperature for another hour, then covered and moved to the fridge.  The next day after I got home from work, I took them out of the fridge 45 minutes before baking (they had been sitting in the fridge for about 20 hours).  I did follow the baking time. 

The spelt flavor was subtle (actually I can hardly taste it), but the texture and the sour flavor were awesome.  

My hand wasn't steady when I did the slashing, so it ended with a "S" opening on the top.  Honestly, I'm still trying to achieve the ear effect...no luck so far...