@cgminds I wish I had an answer for you on that one. Does the newer A11 card have poorer accuracy maps than the A10 card? I wonder if the system just doesn't understand you are trying to roll back the data to an older card. Hypothetically it should read whatever card you have in NAV would not function without a card. Whether it still shows the old card or new card is a good question...but if you remove the card, NAV will not work...so I assume it is reading from the card you have inserted, no matter what the system says you have for a card version.