Today is day 28/21 for my ducklings and layer flock eggs (mix breeds) and day 20 for my Rhodebar eggs.
 
I started with
21 duck eggs, all have developed
10 layer flock eggs, 1 never started the rest have developed
12 Rhodebar eggs, 1 smashed during shipping so I set 11.  4 never started (look like they weren't fertile)
 
And tonight I was sitting in my living room and heard cheeping 

  I never even saw this chick pip, or heard any cheeping from the egg or movement, and I've been checking every couple hours, but when he/she decided it was time they came out in a rush 

  My first layer flock chick has arrived.  Hopefully in the morning there will be more.