I was looking at the operations of QuipuSwap Farm ... @MadFishCommunity

Answer: The delegate selection and vote for tz1ffYUjwjduZkoquw8ryKRQaUjoWJviFVK6 on Dec 17 at 1:22am CST was triggered by the QuipuSwap Farm voting system. According to the voting guide on the QuipuSwap website, users are able to vote for their preferred delegate by sending a transaction to the voting address. The delegate with the most votes is then selected and their address is added to the QuipuSwap Farm operations. This process is repeated every 24 hours to ensure that the delegate selection is kept up to date.

I think I figured it out after checking https://quipuswap.com/voting/vote/tez-KT193D4vozYnhGJQVtw7CoxxqphqUEEwK6Vb_0 and viewing the voting guide there