Silly question on hatch day

[Bantymama]

I have done this many times before but never kept track of exact times. My eggs will be a full 21 days on Feb. 22 at 7:45 am. My question is do they hatch after a full 21 days or sometime during day 21. I usually set mine to so they hatch on sat. or sun. but these were shipped eggs and i set them sooner. I know that some might hatch early and some late. I just want to make sure i am here when it happens. I set on a Friday so they should hatch on friday right.

 

[BantyChickMom]

The typical guideline is they will hatch on the same day of the week they were set, however most of us know there is nothing typical about hatching.