THe same thing happenned again today, with the same deck of auslan_part1. After I’d finished the deck, increased the number of reviews for today, completed them all as verified by the stats screen and the congratulations screen and the deck screen, I went to study another deck and then went outside anki and noticed when I came back, that a backup was completing. At this point the deck screen showed 4 cards due for review in the auslan_part1 deck. I have sync’d and will leave that deck while I study the remainder later today.