Turns out when people say to move cells out of the cell builder 10 days after the grafting day, this means add 9 - not 10 - to the current date. As in, day 1 is graft day. And Day 10 is 9 days later.
Just thought I would share my improved math skills for anyone who may be starting out. I guess everybody has to have that experience sometime.
Interesting note - I saw 2 newly-emerged queens, on combs close to the cell bar. They moved slowly, and were fat. So I actually picked one up to put her in the mating nuc I was setting up! The other got moved with her comb. Sadly, there were 3 more who disappeared into the cell builder. Could be worse - still had 4 queen cells intact. 6 out of 11 is better than no queens in the mating nucs!