Day 29 No External Pips Yet?????

[FluffyDucklings]

I am hatching some cayuga eggs and yesterday was day 28 of incubation. Two eggs hatched but the other 9 or so don't even have external pips yet. I candled them but its hard to tell if they r dead or not but they don't look dead. Could it be that they r just late hatchers? Could it be that they need help getting out? I am new to this forum and this is my first time hatching any kind of egg and i know i should not be able to hatch all of them but hatching only two out of originally 20 seems really off. If anyone can help it would be greatly appreciated

Thanks