That's is a possibility since anyone can take a break and I think it's not written in their ToS that if some users was inactive for a year they cannot claim bonus but I understand too the reason of the DuckDice since the user is inactive there is a lot that happen and of course they need to check whether the user is real or not. I'm not really just sure how they will confirm that it is the same owner and how the owner can confirm that he is the real owner.