My EDD changed 3 times during my first pregnancy and kept freaking me out. It kept going backwards by 2 weeks. Although by 20 weeks my baby was measuring large, but we stayed with my later date (thankfully!!).
In the end, I gave went in labour spontaneously at 39+4 (which would have been 41+4 had we gone by original dates... so I tahnkfully missed out on the 10 day over induction!!).
With DD, I knew my exact dates, but my first scan suggested otherwise. Thankfully I was wiser, and went with the later date, giving myself extra time to get bubs out. I ended up going into labour at 38+4 (which would have been 39+4 had I gone with earlier dates).

It only took me the one pregnancy to work out EDD was an absolute CROCK.
If I was ever to get pregnant again, I'd be doing what I did with DD and giving myself more time to avoid intervention.