@Amy see thats what worries me because it’s my second and they don’t want me going over 39 weeks because I had a c-section with my first and I risk it opening up if I go over.
I think that even based on your math, you'd likely still be okay as well. And as long as your provider knows your history, they will track you and baby as you get nearer to the due date and help you make the best decision for you & baby. They wont knowingly put you or baby at risk.
Honestly its all an estimate. They say, especially if it's your first, to just expect a week plus or minus from ESTIMATED due date....