yep it reminded me of turnips too.. i was actually TTing backwards a day because it was my snowmam's fourth day and i wanted to see if i could prevent her from disappearing to complete the ice set without starting from wall and floor again x.x (maybe i shouldve just went back a few hours instead...) so she was the first one i built and was on day 4 while the boy, man, and tyke were on days 1, 2 and 3 respectively.
i assumed that, worst case scenario, she alone would have melted since the game treats TTing backwards any amount of days as 1 day.. but they were all gone and the card was expired >.<