So I recently used various FFCs expiring in spring and summer of 2025 to book a flight in early spring before changing the flight to a slightly more expensive flight in the fall of 2025. I had intended to take it but about a week after booking I found a better deal with another airline, so I canceled the flight. The FFC credit I got expires 1 year after the purchase date rather than the date of the earliest FFC originally used like before. Seems like a recent-ish change?