As someone who lives in a hot climate where droughts occur regularly and where the groundwater is 80+ degrees in the summer, I’ve been doing mostly no-chill brewing (letting the hot wort passively chill in an HDPE cube overnight then pitching the next day) to reduce my brewing water usage.
I’ve been really happy with the results, and I’m finally beginning to nail hoppy styles. Anyone else have no-chill experience who’d like to compare notes?
IBU production slows down over time. There will be some increase from 60 mins to 120 but the effect will be a lot less than say 40 to 60. Not saying there isn’t a difference, but that it won’t be that great.
See this paper for graphs of IBU production over time of the boil. You will see that almost all of the IBU production is in the first 10-15 mins, then it slows right down.
Obviously your taste is the ultimate decider however. If you find too much bitterness then shorten the boil addition, of course. I always add a 60 minute addition, even if it’s very small (5g for a 25L batch will do).