If I do NIPT and Gender test with Natera at 11weeksand4days. Can the gender be possibly wrong cause it’s still early?

My fetal percentage is 11.4% at 11 weeks and 4days. My OB says if you do it after 10weeks, it’s pretty accurate but I also hear many stories that not until your anatomy scan at 21weeks will be fully confirmed.

Anybody has thoughts if Blood test at 11weeks is more accurate to find the gender or the 21weeks anatomy scan is more accurate?

Thank you ladies.