Medicare Part D Changes for 2025

In the notice of change sent to me by my current Part D insurer, it indicated that Tier 6 drugs are no longer covered in 2025. When I went online to check my drugs, one of my drugs is now Tier 6. So not covered in 2025 and its costly. So I called, and was told that there was an update to the formulary and all Tier 6 drugs will be moved to Tier 3 and therefore covered at the specified level. They are sending me the revised formulary via USPS but they allow 14 business days for delivery, so it could arrive just after open enrollment ends, so too late to switch if it wasn’t reclassified as Tier 3.

1) Any suggestions on how I can verify that my drug will be covered in 2025? (I do plan to make additional calls to see if I get the same message, but that probably doesn’t count as “documentation.”)
2) Should I be concerned that I was told that “all” Tier 6 drugs are moving to Tier 3? That seems odd to me given that there could be drugs that are much more expensive than my prescription and that they would all be moved to Tier 3.