This is my first time trying to figure out Part D (for my wife), so I don't have an answer for you. But I do have an observation ...
I went through the tedious process of entering all her prescriptions via medicare.gov, then sorted the resulting list by total cost. I put the cheapest 12 or so into a spreadsheet, so I could sort them by price (one sort for retail, then sort for mail-order).
A few days later I realized that for any given plan, I could get details of the actual cost for up to 5 pharmacies. But 4 of the plans (namely those from Cigna and Express Scripts) are now showing "N/A" instead of the total cost numbers that I got a few days ago. So for those plans I can't get details of the total cost for each pharmacy.
I got the prices originally on 10/15 or 10/16. Could it be that they were 2020 prices for those 4 plans (even though I said I wanted 2021 prices)? Surely they should have shown "N/A" from the start, rather than displaying incorrect (presumably too low) prices.
How reliable is medicare.gov for this kind of decision? Can I expect the prescription prices to match what they said they would be over the whole of next year?
Any words of wisdom would be appreciated.