Ummmm...assuming you meant 18 days at lockdown. If it's 21 days already they will be popping out any minute now.We just locked down around 5 pm tonight, 12 hours shy of 21 days. I did it a little early since we had a temp spike and a chicken friend told me they might hatch early. So apparently I am going to stare at the incubator for the next 3+ days....and I have two shakers. #4 is also moving! So relieved my daughter didn't kill them!