here is what my opinion is, I think it has to do more with where the eggs are laid and shipped from then incubation process. I have found out that if I ship in eggs for elevation lower them me they weep and hatch rates are way low I shipped in some chicken eggs for LA and had 1 of 12 hatch and 2...
i read it on a website when I was researching quail one night I haven't done it, so I really cant say what way it was done. just they were using in field trials and that the offspring don't reproduce like mules.
take a pair of toe nail clippers and trim the end of beak flat it will bleed a little don't worry about it it will cure the egg breaking it will hurt her to crack the eggs with her beak
here is some thing that can help you https://www.backyardchickens.com/t/16008/how-to-tell-a-fertile-vs-infertile-egg-pictures in this link you will see photos of fertile chicken eggs quail are the same.
on quail usually wait for first 3 eggs from hen the eggs get to full size and chicks will be bigger and healthier, also first eggs might not be fertile
if the pullets are eating laying feed they can start laying eggs most likely the egg will not have a Yoke in it. and if you continue the laying feed there is a high possibility that you can ruin the egg production of the pullets. so be careful of what you are doing with your young pullets.
totally agree with titika more eggs are better then few at a time you can store eggs in carton for 6 days then incubate. your hatch rate should be just fine if the incubator is set right. as the brooder goes tote is fine as long as you aren't overcrowding them I use biggest tote you can get at...