They can be left with the mother the entire time if your temps are right. I dont recommend it personally... But just saying.
Hours are nothing, they will be fine for a couple days even. Just the other day i had a female laying when i woke up to go to work. I knew she wasnt done so i just left her and came home 10 hours to her around 8 eggs. Yes they were stuck together by then but that makes no difference.
Ive even gone away for a weekend and come back to eggs that eventually hatched perfectly!
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