wow..I didn't know about lockdown..not even sure what it is! Guessing you are not to open the bator at all from day 18?? I opened it a lot, and I mean a lot. The chicks kept messing with the other eggs! Got 60% hatching..never candled. One didn't make it I believe because when it pipped a live one in there turned it up side down..and it drowned. Next batch I will keep it closed..But stil might remove hatched chicks!
