The rather abrupt end of Fairmont President's Club. They announeced in late 2017 (after people had already been making bookings for 2018) that it will be merged into Accor in July 2018.
Originally, even if you did enough stays in the first half of 2018 to requalify status for 2019, such stays would have earned nothing, but they have back-tracked a little bit, and will offer some stub-year benefits that will expire in Feb 2019.