The Prime Minister's resignation date has been brought forward by 2 days, according to the latest Polymarket data. Starmer is now expected to step down on 16 September 2026, rather than the previous date of 17 September.
The shift in the implied resignation date suggests increased market confidence that Starmer will depart Downing Street in the coming months. The probability of Starmer remaining PM on 16 Sept 2026 is now estimated at ~86%.