Well most of the ones hatched this batch were already pipped on day 17. I went to candle Thursday night as I couldn't do it Friday(lockdown day) as I had plans away all day. To my amazement their were over 10 externally pipped, so took off turner and took out dividers. This incubator was my Brinsea Eco 20 which always hatches early, I'm blaming it on a little higher temp. My home made foam one with the hova turner in it is on time but when I checked my other home made bator I found most of the EE had externally pipped also. That bator also runs a little higher on the temps as it's run with a baseboard heater thermostat. I was also told if you do run a little higher temp that your chicks will be pullets, so this could explain my extremely high pullet count this year. I also have a few hundred in my old Jamesway industrial bator I picked up a few months ago and those are all on time for growth as I'm just running at the mark as it was hard to get the temps up on it so I threw in another heater from a spare on the bottom. My eggs are collected daily and they are penned so I never find some stashed away anywhere to not have my dates right. However this last hatch I had the eggs sitting on my counter for about 13 days as I had no incubator room from the previous hatches in between setting up the new bators. They will never sit that long now that I have room but I've had them sit out for over 2 weeks before and had them hatch perfectly fine. I know some say they aren't viable after 7 days but that is just not true.
I'm thinking my temps are playing a part. I have a still air incubator that I run at 101, when I ran it at 99-100 my hatches were 3-4 days late and I had a lot of them fully formed but not pipping. Bumped the temps up and they started hatching on day 21. We've had some crazy weather lately though, so it's possible the temperature in the bedroom has fluctuated and effected the incubator temps. I've just been checking the temps in the evenings, so ...
As I was taking the turner and 2 chicks out, I noticed another egg had externally pipped so I suspect when I go back tomorrow or Monday (I'm not currently staying at that house full time) I'll have a bunch more chicks running around.
And my broody Wyandotte has an external pip, so she may have a few of her own by tomorrow. She's only sitting on 5 eggs, she rejected a few as they were developing, so I may try to slip a few extra chicks under her. We'll see.