@lichan, the first thing you need is this:
It arrives on our doorsteps (PO Boxes in my case) before October 1, sign-up date. New signees don’t get the printed version before the process of signing up has completed; I didn’t get my first copy until around July, I wish I had. You should find it online (no one told me about it!)
Go to page 79 (start of Section 5). Read the whole section. Regard it as homework with a really stupid multiple choice afterward, “What does it say in bold black print first on page 79?”) Fail the exam and you pay for the remainder of your life.
Then the three other lines in bold black on that page. The table on the next page (page 80) answers your question:
It’s easy; scan down the “F” and “G” columns; the only difference is “Medicare Part B deductible”, which is not known yet; it will not be known until around November, if then. Nevertheless it is not hard to see if an “F” costs around $300 more than a “G” “G” is cheaper next year. Same for “C” and “D”. See the same table.
For those who don’t understand what I just said talk to SHIP (SHIPA, or whatever it is called.)
Bear in mind that those on “F” and “C” might have an interest in the Part B deductible going up as much as is possible, or more; it’s a competition. If you get the “F” you might pay more today and less in 2028. We can change down but we can never change up because we are diabetics.

