I suppose I could have the bot look at
anime.stackexchange.com/users?tab=voters&filter=week and check whether there are any differences from the previous day, and then just grab those. That would miss some edge cases (e.g. cancelling the same number of votes as you cast in a day, or people who don't vote very much) but it should catch most of the interesting content, and the rest can go on a 24 hr rotation.