Hunch. On 6 October Alito said he intends to stay through this court year, which ends in summer 2027.
The 31 December market resolves YES if by 23:59 US Eastern time on 31 December 2026 a US Supreme Court press release, or Samuel Alito himself, announces that he will leave the court, whatever the date of the exit. The Guardian, Reuters or BBC News confirm it, and two of them settle it if the court's page cannot be opened.
We looked for cases where a US Supreme Court judge aged 75 or more was openly asked about retiring in an election year, while the president and the Senate were from the party that appointed the judge, and the judge did not leave at the end of the June term. We found nine such judges from 1924 to 2014. Felix Frankfurter left in August 1962, and none of the other eight announced an exit from late October to New Year.