Rookie question re:turning eggs

Hi,
My daughter came home with a dozen eggs from a sleepover two weeks ago with no info. I have a homemade bator and have been turning them about 4x a day. Well I wasn't expecting anything until next weekend since she said they had just been taken from the nest. Apparently some had already been in the nest a week as they started hatching 2 days ago. I read in one place to turn until day 18 and another said you didn't need to turn the last week. I was going to stop turning because most are probably older than we thought. 7 have hatched so far and the only info I have is the hens were big and black, half the chicks look like pics I have seen of black australorp, the other half are grey/silver and yellow. We have no idea what the rooster was, he was killed (by dog)2 days before she got the eggs. So my question is, is it ok to stop turning?
Thanks,
Krista