Yes. In my 2 hatches I had quite a number of babies hatch overnight and remain perfectly healthy and happy in the incubator.
Remember, they have a 3 day supply of yolk.
In my first batch I had one hatch a day early and one hatch a day late.
On advice, I shuffled my eggs around several times during incubation for the second hatch and they all arrived within about 18 hours of each other.
I'm sorry, I have been sick for a full month as of today and completely missed following your classroom hatch-a-long. :(
I found that the light on my phone worked better for candling the dark and blue/green eggs than the candler on the NR360.
It also helped to shut myself into a closet for...