so confused about segment rates

I am doing some modelling trying to forecast the segment rates for 2024 EOY valuation.  I am getting 4.75/4.96/5.59 for 430 and 5.03/5.27/5.23 for 404.  Leaving the technicalities apart, thus my conclusion is that for 2024 the min and max are the same and are driven by 430 rates.  This is totally insane, what am I missing?

I don't think you are missing anything.

With the cushion, I don't think min and max will always be the same but yes you will have situations where the max deductible is driven by the minimum required.  I haven't read the preambles to the regs, but I'd be surprised if there was much thought given to this directional change in interest rates back when they were issued.

cushion does not exist for a start-up CB plan unless you get funky.  Just trying to get my framework together on how to consult for a start-ups in 2024....

Yes for startups, I agree - that you're probably looking at the same min max with that interest rate projection for 1st year on a CB plan.

Your segment rates for 430 should be  5.03/5.27/5.59, because the first two 404 rates fall within the 95%-105% corridor of the 25-year average segment rates.

.....  Jeff