This recently (Oct 17) worked for me.

-- FFC expiring ~ Nov 2024
-- Bought new flight ~ Sep 2024 (legit intent to travel)
-- Plans changed, research here to find a way to salvage FFC value
-- Changed to fully refundable flight that used all the FFC and needed a tiny top up CC payment ~ late Sept
-- Changed to the absolute cheapest flight I could find ~ early Oct
-- Website indicated refund from change (most of the original FFC value) would be refunded to card ending .... used for top-up
-- That amount did post to the CC account within a few days

I'm only "out" the value of the super cheapo flight I changed to (under $150) and cashed out most of the FCC as a CC refund.

(EDIT: if it matters, the top-up CC was the same CC as used for the initial/original flight purchase that ended up as a FFC.)