Hop Utilitization with LME late additions

I am using 9 lbs of LME, adding 6 @ 15 min. What kid of adjustment do I need to make to IBU with lower gravity wort? Advice would be appreciated!

Do the IBU calculations for the early hops with the wort at the lower gravity and if you’re adding hops after the LME late addition, use the higher gravity for those IBUs. You could ignore the second part if you like, won’t make much difference.

Shadetree your a wealth of knowledge… I did that actually. I will ignore the end of boil additions! It seemed logical but I just needed someone to verify! Thank you!

I never adjusted for this, always just kept it the same, and thought of the late lme addition as an attempt to get a truer color and less carmelization, which in turn probably leads to a perceived sense of “more bitterness” given that less of the extract was boiled for the full hour.