It is possible Houck’s value changes for the better. As far as I can tell, they update players all the time and it doesn’t happen all at once with some mass update. As player projections for performance and salary change, they use them to create new values.
When that website first started, they were updating multiple times per year including in August/ September, which they stopped when one annoying poster named Notin told them to just skip late season updates for periods when trades weren’t allowed anyway and go right to off-season values...