If you set them on Sunday the 9th
On Monday, the 10th, they have 1 day of development.
OnTuesday the 11th, they have 2 days of development.
On Wednesday the 12th, they have 3 days of development.
.....
On Thursday the 27th, they have 18 days of development, so this is lockdown.
If your temperatures are perfect, then they should hatch after 21 days of development, which is Sunday the 30th. Notice, you set them on a Sunday, they should hatch on a Sunday.
I don't think hitting lockdown dead square perfect is all that critical. Those eggs are pretty tough and many eggs are going to hatch a little early or late. They do not all hatch at exactly the same time. I think it is good practice to try to get it right, but if you are off a few hours, I would not worry too much.
I've had an incubator running a little warm so when I went into lockdown after 18 days of development, I had one egg already pipping. By the time they had 19 days of development, I had 4 chicks running around in the incubator. By the time I had 20 days of development, I had a total of 15 chicks playing rugby in the incubator and having a great time.
On Monday, the 10th, they have 1 day of development.
OnTuesday the 11th, they have 2 days of development.
On Wednesday the 12th, they have 3 days of development.
.....
On Thursday the 27th, they have 18 days of development, so this is lockdown.
If your temperatures are perfect, then they should hatch after 21 days of development, which is Sunday the 30th. Notice, you set them on a Sunday, they should hatch on a Sunday.
I don't think hitting lockdown dead square perfect is all that critical. Those eggs are pretty tough and many eggs are going to hatch a little early or late. They do not all hatch at exactly the same time. I think it is good practice to try to get it right, but if you are off a few hours, I would not worry too much.
I've had an incubator running a little warm so when I went into lockdown after 18 days of development, I had one egg already pipping. By the time they had 19 days of development, I had 4 chicks running around in the incubator. By the time I had 20 days of development, I had a total of 15 chicks playing rugby in the incubator and having a great time.
