I had a similar concern a couple of years ago about obsolescence and my Aurora Lynx FW converter. I decided to try to get out from underneath the burgeoning threat got a Lynx AES16e AES/EBU pcie card. It turned out to be a good decision as when I put together the X99 rig I didn’t have to worry about the absence of FW. They are reasonably well-priced and very high quality cards.