Ovulation day vs LMP to track pregnancy?

I have long cycles, so my pregnancy tracking and due date are quite different if I use my LMP vs my O day. LMP puts me at 5+1 due October 14. O day puts me at 4+2 due October 20. I’m assuming since many people don’t track their ovulation and it can be difficult to pinpoint your exact ovulation day, that makes LMP the popular option. But if you have a rough idea of your O day, is it more accurate to go by that?