Deductions & credits

I understand this is how the IRS does it but it makes no sense.  Why not use a predicted number that's for the year actually in use?  Anyway, you wouldn't need the number until tax filing time, so for example by 2025 filing deadline the 2024 value should be available.  Why compare 2024 income to 2023 FPL?  You should be eligible for the subsidy in the year that you use it.