All the eggs are from the same duck hen, from the same week! I don't know why the air cells are different sizes. Some look like day 20 cells and it's day 25 Others seem like 1/3 the egg. This is my first hatch from home birds. Crossing my fingers everything works out properly!!
I have not ever hatched duck eggs. tried it on shipped eggs last spring and it did not go well. On chicken eggs, I do not look at the air cells. If they have developed I put them in the hatcher and cross my fingers. The air cells would drive me mad if I looked at them too much. Good luck!
Don't worry about the different sizes unless it's obvious that there's a problem, all of the eggs are not the same and you have to consider that the temp is a little different in parts of the bator or under the broody which means some will develope a little slower or faster than the rest. This whole incubation thing is about learning as you go and continue learning as you go.
