I had my appt on Monday. I have 19 days left and I had practice contractions last week (I'm calling them that because they huuuuurt, not just pressure like regular BH). My OB said well, 3 hours of practicing didin't do anything. I'm 0 cm and my cervix isn't even soft.
My mom went into labor 2 weeks early with no dilation. She woke up in a puddle one morning after her water broke and then she had me 3 hours later.
Same thing with my brother. Water broke and she had him a few hours later (two weeks early).
A friend of mine was dilated 3 cm for nearly 2 weeks and went overdue and was induced. So everyone is different. I don't even know why they check, really.