Lockdown but half full (not including air sac) eggs with movement???

[Egg_newton]

It is day 18. We were candling to move everyone out of the turner and noticed a few eggs that were not completely full but still had definate movement insode of them. Most of the eggs looked right all full except for the air sac. What does this mean? Really small chicks? Some are really far behind in development? Wat? SOme of the eggs are mixed but all hens and roosters are standard sized so it isn't the case of bantam roo/std hen.

anyone else have a similar experience?

 

[chicken_china_mom]

I have had some eggs that the fetus growing inside didn't look ready to be placed in lockdown, but some chicks just grow rapidly those last 48 to 62 hours before hatching. I just put eggs in lockdown day before yesterday and they started hatching the next morning, even though they didn't look ready. But here they come, nonetheless! If they're moving around I don't think you have anything to worry about. They will catch up in the next day or so.