@WCF I'm new here, read your post. I'm in the same boat as your fiancée. The difference is that my visa category is EB2 (employment-based). I had my interview on 10/9 and was told that my visa is approved and to wait for a couple of weeks for my visa packet to be delivered. It's been 2 long weeks but my CEAC status is still "ready" and the dates just keeps changing.
I tried to call the embassy, and all they could say was that they were working on my case since the dates had been updated five times since the interview date, and that all I needed to do was wait. My medical expiry is Dec 18. 🫣
Did you have any updates?