Babies measuring bigger

Just curious if anyone has had a baby measure bigger and they changed your due date (mine was only by 4 days) but 4 days in my world is a lot when out and about super busy with my other kids and planning if I'm going to certain events with them. Not that the baby ever comes on the due date, totally know we can't 100% prepare haha but my question is for those that have had their due date moved did you end up delivering closer to the new due date or original. My understanding is when the baby is in the first trimester and they ultra sound that is the most accurate for how far along you are because every baby during that the measures the same based on how old they are. Once in 2nd trimester genetics play a roll. My daughter is measuring a week ahead now, but I'm 5'7" and dad is 6'2" so we could just be having a long baby.  Anyways I was just curious to hear other's stories. :)